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    <dei:EntityRegistrantName contextRef="Context">FRANKLIN  U.S. GOVERNMENT MONEY FUND</dei:EntityRegistrantName>
    <rr:RiskReturnHeading contextRef="Context_S000006859Member_S000006859Summary1Member">FRANKLIN U.S. GOVERNMENT MONEY FUND</rr:RiskReturnHeading>
    <rr:ProspectusDate contextRef="Context">2023-11-01</rr:ProspectusDate>
    <rr:ObjectiveHeading contextRef="Context_S000006859Member_S000006859Summary1Member">
 Investment Goal</rr:ObjectiveHeading>
    <rr:ObjectivePrimaryTextBlock contextRef="Context_S000006859Member_S000006859Summary1Member">&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;To provide investors with as high a level
of current income as is consistent with the preservation of shareholders&#x2019; capital and liquidity. The
Fund also tries to maintain a stable $1.00 share price. &lt;/p&gt;</rr:ObjectivePrimaryTextBlock>
    <rr:ExpenseHeading contextRef="Context_S000006859Member_S000006859Summary1Member">
Fees and Expenses of the Fund</rr:ExpenseHeading>
    <rr:ExpenseNarrativeTextBlock contextRef="Context_S000006859Member_S000006859Summary1Member">&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;These tables describe the fees and expenses
that you may pay if you buy and hold shares of the Fund.&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Please note that the tables and examples
below do not reflect any transaction fees that may be charged by financial intermediaries, or commissions
that a shareholder may be required to pay directly to its financial intermediary when buying or selling
Class R6 or Class A shares.&lt;/p&gt;</rr:ExpenseNarrativeTextBlock>
    <rr:ShareholderFeesCaption contextRef="Context_S000006859Member_S000006859Summary1Member">Shareholder Fees</rr:ShareholderFeesCaption>
    <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
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      unitRef="pure">0</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
    <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
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      unitRef="pure">0</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
    <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
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      unitRef="pure">0</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
    <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
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      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
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      unitRef="pure">0</rr:MaximumDeferredSalesChargeOverOfferingPrice>
    <rr:MaximumDeferredSalesChargeOverOfferingPrice
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
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      unitRef="pure">0.0100</rr:MaximumDeferredSalesChargeOverOfferingPrice>
    <rr:MaximumDeferredSalesChargeOverOfferingPrice
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0</rr:MaximumDeferredSalesChargeOverOfferingPrice>
    <rr:MaximumDeferredSalesChargeOverOfferingPrice
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0</rr:MaximumDeferredSalesChargeOverOfferingPrice>
    <rr:OperatingExpensesCaption contextRef="Context_S000006859Member_S000006859Summary1Member">Annual Fund
Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)</rr:OperatingExpensesCaption>
    <rr:ManagementFeesOverAssets
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:ManagementFeesOverAssets
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:ManagementFeesOverAssets
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:ManagementFeesOverAssets
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0015</rr:ManagementFeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0065</rr:DistributionAndService12b1FeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0050</rr:DistributionAndService12b1FeesOverAssets>
    <rr:DistributionAndService12b1FeesOverAssets
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_35_"
      unitRef="pure">0.0036</rr:OtherExpensesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_36_"
      unitRef="pure">0.0036</rr:OtherExpensesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_37_"
      unitRef="pure">0.0036</rr:OtherExpensesOverAssets>
    <rr:OtherExpensesOverAssets
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_38_"
      unitRef="pure">0.0034</rr:OtherExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_39_"
      unitRef="pure">0.0051</rr:ExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_40_"
      unitRef="pure">0.0116</rr:ExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_41_"
      unitRef="pure">0.0101</rr:ExpensesOverAssets>
    <rr:ExpensesOverAssets
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_42_"
      unitRef="pure">0.0049</rr:ExpensesOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssets
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_43_"
      unitRef="pure">0</rr:FeeWaiverOrReimbursementOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssets
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_44_"
      unitRef="pure">0</rr:FeeWaiverOrReimbursementOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssets
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_45_"
      unitRef="pure">0</rr:FeeWaiverOrReimbursementOverAssets>
    <rr:FeeWaiverOrReimbursementOverAssets
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_46_"
      unitRef="pure">-0.0003</rr:FeeWaiverOrReimbursementOverAssets>
    <rr:NetExpensesOverAssets
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_47_"
      unitRef="pure">0.0051</rr:NetExpensesOverAssets>
    <rr:NetExpensesOverAssets
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_48_"
      unitRef="pure">0.0116</rr:NetExpensesOverAssets>
    <rr:NetExpensesOverAssets
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_49_"
      unitRef="pure">0.0101</rr:NetExpensesOverAssets>
    <rr:NetExpensesOverAssets
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_50_"
      unitRef="pure">0.0046</rr:NetExpensesOverAssets>
    <rr:ExpenseExampleHeading contextRef="Context_S000006859Member_S000006859Summary1Member">Example</rr:ExpenseExampleHeading>
    <rr:ExpenseExampleNarrativeTextBlock contextRef="Context_S000006859Member_S000006859Summary1Member">&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;This Example is intended
to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.
The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem
all of your shares at the end of the period. The Example also assumes that your &lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;investment
has a 5% return each year and that the Fund's operating expenses remain the same. The Example reflects
adjustments made to the Fund&#x2019;s operating expenses due to the fee waivers and/or expense reimbursements
by management for the 1 Year numbers only. Although your actual costs may be higher or lower, based on
these assumptions your costs would be:&lt;/p&gt;</rr:ExpenseExampleNarrativeTextBlock>
    <rr:ExpenseExampleYear01
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">52</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">163</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">284</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">639</rr:ExpenseExampleYear10>
    <rr:ExpenseExampleYear01
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">218</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">368</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">637</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">1226</rr:ExpenseExampleYear10>
    <rr:ExpenseExampleYear01
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">103</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">321</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">557</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">1234</rr:ExpenseExampleYear10>
    <rr:ExpenseExampleYear01
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">47</rr:ExpenseExampleYear01>
    <rr:ExpenseExampleYear03
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">154</rr:ExpenseExampleYear03>
    <rr:ExpenseExampleYear05
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">271</rr:ExpenseExampleYear05>
    <rr:ExpenseExampleYear10
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">612</rr:ExpenseExampleYear10>
    <rr:ExpenseExampleNoRedemptionByYearCaption contextRef="Context_S000006859Member_S000006859Summary1Member">If
you do not sell your shares:</rr:ExpenseExampleNoRedemptionByYearCaption>
    <rr:ExpenseExampleNoRedemptionYear01
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">118</rr:ExpenseExampleNoRedemptionYear01>
    <rr:ExpenseExampleNoRedemptionYear03
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">368</rr:ExpenseExampleNoRedemptionYear03>
    <rr:ExpenseExampleNoRedemptionYear05
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">637</rr:ExpenseExampleNoRedemptionYear05>
    <rr:ExpenseExampleNoRedemptionYear10
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="usd">1226</rr:ExpenseExampleNoRedemptionYear10>
    <rr:StrategyHeading contextRef="Context_S000006859Member_S000006859Summary1Member">
Principal Investment Strategies</rr:StrategyHeading>
    <rr:StrategyNarrativeTextBlock contextRef="Context_S000006859Member_S000006859Summary1Member">&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The Fund is a &#x201c;feeder fund&#x201d; that invests,
through the Master Portfolio, at least 99.5% of its total assets in Government securities, cash and repurchase
agreements collateralized fully by Government securities or cash. For purposes of this policy, &#x201c;Government
securities&#x201d; means any securities issued or guaranteed as to principal or interest by the United States,
or by a person controlled or supervised by and acting as an instrumentality of the Government of the
United States pursuant to authority granted by the Congress of the United States; or any certificate
of deposit for any of the foregoing. Government securities include those issued by government agencies
or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), Federal Home Loan
Mortgage Corporation (Freddie Mac), Federal Home Loan Banks and Federal Farm Credit Banks, whose securities
are neither issued nor guaranteed by the U.S. Government. The Fund intends to be a &#x201c;Government money
market fund,&#x201d; as such term is defined in or interpreted under Rule 2a-7 under the Investment Company
Act of 1940. Shareholders will be given at least 60 days&#x2019; advance notice of any change to the 99.5%
policy.&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The Fund uses the amortized cost method of valuation to seek to maintain a stable
$1.00 share price.&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Unless the context otherwise requires, references to the Fund&#x2019;s investments
refer to those investments of the Master Portfolio to which the Fund is exposed and references to the
investment manager or the Fund&#x2019;s investment manager refer to the Master Portfolio&#x2019;s investment manager.&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The
Fund invests in:&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;U.S.
government securities&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; which may include fixed, floating and variable rate securities.&lt;/span&gt;&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;Repurchase
agreements&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; which are agreements by the Fund to buy Government securities from a broker-dealer
or other counterparty and then to sell the securities back to such counterparty on an agreed upon date
(generally, less than seven days) at a higher price, which reflects prevailing short-term interest rates.&lt;/span&gt;&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;Portfolio
maturity and quality&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; The Fund only buys securities that the investment manager determines present
minimal credit risks. The Fund maintains a dollar-weighted average portfolio maturity of 60 calendar
days or less, maintains a dollar-weighted average life for its portfolio of 120 calendar days or less,
and only buys securities that mature or are deemed to mature in 397 calendar days or less.&lt;/span&gt;&lt;/p&gt;</rr:StrategyNarrativeTextBlock>
    <rr:RiskHeading contextRef="Context_S000006859Member_S000006859Summary1Member">
 Principal Risks</rr:RiskHeading>
    <rr:RiskNarrativeTextBlock contextRef="Context_S000006859Member_S000006859Summary1Member">&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;You could lose money by
investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per
share, it cannot guarantee it will do so. An investment in the Fund is not a bank account and is not
insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The
Fund&#x2019;s sponsor is not required to reimburse the Fund for losses, and you should not expect that the
sponsor will provide financial support to the Fund at any time, including during periods of market stress.&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Interest
Rate:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;
 When interest rates rise, debt security prices generally fall. The opposite is also generally true:
debt security prices rise when interest rates fall. Interest rate changes are influenced by a number
of factors, including government policy, monetary policy, inflation expectations, perceptions of risk,
and supply of and demand for debt securities.  The Fund's yield will vary. A low interest rate environment
may prevent the Fund from providing a positive yield or paying Fund expenses out of current income and
could impair the Fund's ability to maintain a stable net asset value. A sharp and unexpected rise in
interest rates could cause the Fund's share price to drop below a dollar. In general, securities with
longer maturities or durations are more sensitive to these interest rate changes. &lt;/span&gt;&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Credit:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;
 U.S. government investments generally have the least credit risk but are not completely free of credit
risk. The Fund may incur losses on debt securities that are inaccurately perceived to present a different
amount of credit risk by the market, the investment manager or the rating agencies than such securities
actually do. Any downgrade of securities issued by the U.S. government may result in a downgrade of securities
issued by its agencies or instrumentalities.&lt;/span&gt;&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Income:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  Because the Fund can
only distribute what it earns, the Fund's distributions to shareholders may decline when prevailing interest
rates fall. &lt;/span&gt;&lt;/p&gt;

&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Because
the Fund limits its investments to high-quality, short-term securities, its portfolio generally will
earn lower yields than a portfolio with lower-quality, longer-term securities subject to more risk.&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;U.S.
Government Securities:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  Not all obligations of the U.S. Government, its agencies and instrumentalities
are backed by the full faith and credit of the United States. Some obligations are backed only by the
credit of the issuing agency or instrumentality, and in some cases there may be some risk of default
by the issuer. Government agency or instrumentality issues have different levels of credit support. &lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;U.S.
government-sponsored entities ("GSEs"), such as Fannie Mae and Freddie Mac, may be chartered by Acts
of Congress, but their securities are neither issued nor guaranteed by the U.S. government. Although
the U.S. government has provided financial support to Fannie Mae, Freddie Mac and certain other GSEs,
no assurance can be given that the U.S. government will continue to do so.&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; Accordingly, securities
issued by Fannie Mae and Freddie Mac may involve a risk of non-payment of principal and interest. Investors
should remember that guarantees of timely repayment of principal and interest do not apply to the market
prices and yields of the securities or to the net asset value or performance of the Fund, which will
vary with changes in interest rates and other market conditions.&lt;/span&gt;&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Repurchase
Agreements:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  A repurchase agreement exposes the Fund to the risk that the party that sells
the securities to the Fund may default on its obligation to repurchase such securities.&lt;/span&gt;&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Market:
 &lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;The
market values of securities or other investments owned by the Fund will go up or down, sometimes rapidly
or unpredictably. The market value of a security or other investment may be reduced by market activity
or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all
investments. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more
buyers than sellers, prices tend to rise.&lt;/span&gt;&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The global outbreak of the novel strain of coronavirus, COVID-19
and its subsequent variants, has resulted in market closures and dislocations, extreme volatility, liquidity
constraints and increased trading costs. The long-term impact on economies, markets, industries and individual
issuers is not known. Some sectors of the economy and individual issuers have experienced or may experience
particularly large losses. Periods of extreme volatility in the financial markets; reduced liquidity
of many instruments; and disruptions to supply chains, consumer demand and employee availability, may
continue for some time.&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Master/Feeder Structure:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  The Fund seeks to
achieve its investment goal by investing all of its assets in shares of the Master Portfolio. The Master
Portfolio has the same investment goal and policies as the Fund. The Fund buys shares of the Master Portfolio
at net asset value. An investment in the Fund is an indirect &lt;/span&gt;&lt;/p&gt;

&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;investment
in the Master Portfolio. It is possible that the Fund may have to withdraw its investment in the Master
Portfolio if the Master Portfolio changes its investment goal or if the Fund&#x2019;s board of trustees, at
any time, considers it to be in the Fund&#x2019;s best interest.&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Management:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  The Fund is subject
to management risk because it is an actively managed investment portfolio. The investment manager applies
investment techniques and risk analyses in making investment decisions for the Master Portfolio, but
there can be no guarantee that these decisions will produce the desired results.&lt;/span&gt;&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Cybersecurity:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;
 Cybersecurity incidents, both intentional and unintentional, may allow an unauthorized party to gain
access to Fund assets, Fund or customer data (including private shareholder information), or proprietary
information, cause the Fund, the investment manager, authorized participants, or index providers (as
applicable) and listing exchanges, and/or their service providers (including, but not limited to, Fund
accountants, custodians, sub-custodians, transfer agents and financial intermediaries) to suffer data
breaches, data corruption or loss of operational functionality or prevent Fund investors from purchasing,
redeeming shares or receiving distributions. The investment manager has limited ability to prevent or
mitigate cybersecurity incidents affecting third party service providers, and such third party service
providers may have limited indemnification obligations to the Fund or the investment manager. Cybersecurity
incidents may result in financial losses to the Fund and its shareholders, and substantial costs may
be incurred in an effort to prevent or mitigate future cybersecurity incidents. Issuers of securities
in which the Fund invests are also subject to cybersecurity risks, and the value of these securities
could decline if the issuers experience cybersecurity incidents.&lt;/span&gt;&lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Because technology is
frequently changing, new ways to carry out cyber attacks are always developing. Therefore, there is a
chance that some risks have not been identified or prepared for, or that an attack may not be detected,
which puts limitations on the Fund's ability to plan for or respond to a cyber attack. Like other funds
and business enterprises, the Fund, the investment manager, and their service providers are subject to
the risk of cyber incidents occurring from time to time.&lt;/p&gt;</rr:RiskNarrativeTextBlock>
    <rr:RiskLoseMoney contextRef="Context_S000006859Member_S000006859Summary1Member">You could lose money by
investing in the Fund.</rr:RiskLoseMoney>
    <rr:RiskMoneyMarketFundMayNotPreserveDollar contextRef="Context_S000006859Member_S000006859Summary1Member">Although the Fund seeks to preserve the value of your investment at $1.00 per
share, it cannot guarantee it will do so.</rr:RiskMoneyMarketFundMayNotPreserveDollar>
    <rr:RiskNotInsured contextRef="Context_S000006859Member_S000006859Summary1Member">An investment in the Fund is not a bank account and is not
insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</rr:RiskNotInsured>
    <rr:BarChartAndPerformanceTableHeading contextRef="Context_S000006859Member_S000006859Summary1Member">
Performance</rr:BarChartAndPerformanceTableHeading>
    <rr:PerformanceNarrativeTextBlock contextRef="Context_S000006859Member_S000006859Summary1Member">&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The following bar chart and table provide some indication
of the risks of investing in the Fund. The bar chart shows changes in the Fund's performance from year
to year for Class A shares. The table shows the Fund's average annual returns for 1 year, 5 years, 10
years or since inception, as applicable. The Fund's past performance is not necessarily an indication
of how the Fund will perform in the &lt;/p&gt;&lt;p style="font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;future.
You can obtain updated performance information at franklintempleton.com or by calling (800) DIAL BEN/342-5236.&lt;/p&gt;</rr:PerformanceNarrativeTextBlock>
    <rr:PerformancePastDoesNotIndicateFuture contextRef="Context_S000006859Member_S000006859Summary1Member">The Fund's past performance is not necessarily an indication
of how the Fund will perform in the future.</rr:PerformancePastDoesNotIndicateFuture>
    <rr:PerformanceAvailabilityWebSiteAddress contextRef="Context_S000006859Member_S000006859Summary1Member">franklintempleton.com</rr:PerformanceAvailabilityWebSiteAddress>
    <rr:PerformanceAvailabilityPhone contextRef="Context_S000006859Member_S000006859Summary1Member">(800) DIAL BEN/342-5236</rr:PerformanceAvailabilityPhone>
    <rr:BarChartHeading contextRef="Context_S000006859Member_S000006859Summary1Member">Class A Annual Total Returns</rr:BarChartHeading>
    <rr:BarChartClosingTextBlock contextRef="Context_S000006859Member_S000006859Summary1Member">&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse" width="100%"&gt;&lt;tr style="font-size:1pt;"&gt;&lt;td style="width:17.33%;"&gt;&#160;&lt;/td&gt;&lt;td style="width:68%;"&gt;&#160;&lt;/td&gt;&lt;td style="width:14.67%;"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;"&gt;Best Quarter: &lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;2019, Q2&lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;0.46%&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;"&gt;Worst Quarter: &lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;2021, Q3&lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;0.00%&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;table cellpadding="2" cellspacing="0" style="border-collapse:collapse" width="100%"&gt;&lt;tr style="font-size:1pt;"&gt;&lt;td style="width:100%;"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; font-size:1pt;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;"&gt;As
of September 30, 2023, the Fund&#x2019;s year-to-date return was 3.32%.&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;</rr:BarChartClosingTextBlock>
    <rr:HighestQuarterlyReturnLabel contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member">Best Quarter</rr:HighestQuarterlyReturnLabel>
    <rr:BarChartHighestQuarterlyReturnDate contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member">2019-06-30</rr:BarChartHighestQuarterlyReturnDate>
    <rr:BarChartHighestQuarterlyReturn
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0046</rr:BarChartHighestQuarterlyReturn>
    <rr:LowestQuarterlyReturnLabel contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member">Worst Quarter</rr:LowestQuarterlyReturnLabel>
    <rr:BarChartLowestQuarterlyReturnDate contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member">2021-09-30</rr:BarChartLowestQuarterlyReturnDate>
    <rr:BarChartLowestQuarterlyReturn
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0000</rr:BarChartLowestQuarterlyReturn>
    <rr:YearToDateReturnLabel contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member">As
of September 30, 2023, the Fund&#x2019;s year-to-date return was 3.32%.</rr:YearToDateReturnLabel>
    <rr:BarChartYearToDateReturnDate contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member">2023-09-30</rr:BarChartYearToDateReturnDate>
    <rr:BarChartYearToDateReturn
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0332</rr:BarChartYearToDateReturn>
    <rr:PerformanceTableHeading contextRef="Context_S000006859Member_S000006859Summary1Member">Average
Annual Total Returns For periods ended December 31, 2022</rr:PerformanceTableHeading>
    <rr:AverageAnnualReturnYear01
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    <rr:AverageAnnualReturnYear05
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
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      unitRef="pure">0.0087</rr:AverageAnnualReturnYear05>
    <rr:AverageAnnualReturnYear10
      contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member"
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      unitRef="pure">0.0047</rr:AverageAnnualReturnYear10>
    <rr:AverageAnnualReturnYear01
      contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      unitRef="pure">0.0083</rr:AverageAnnualReturnYear01>
    <rr:AverageAnnualReturnSinceInception
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    <rr:AverageAnnualReturnYear01
      contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member"
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    <rr:AverageAnnualReturnSinceInception
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    <rr:AverageAnnualReturnYear01
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
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    <rr:AverageAnnualReturnYear05
      contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member"
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    <rr:AverageAnnualReturnSinceInception
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    <dei:DocumentType contextRef="Context">485BPOS</dei:DocumentType>
    <dei:DocumentPeriodEndDate contextRef="Context">2023-06-30</dei:DocumentPeriodEndDate>
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    <dei:DocumentCreationDate contextRef="Context">2023-10-26</dei:DocumentCreationDate>
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    <rr:AnnualReturn2019
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    <rr:AnnualReturn2020
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    <rr:AnnualReturn2021
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    <rr:AnnualReturn2022
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    <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="Context_C000018536Member_S000006859Member_S000006859Summary1Member">October 31, 2024</rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="Context_C000213872Member_S000006859Member_S000006859Summary1Member">October 31, 2024</rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="Context_C000213873Member_S000006859Member_S000006859Summary1Member">October 31, 2024</rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
    <rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination contextRef="Context_C000128781Member_S000006859Member_S000006859Summary1Member">October 31, 2024</rr:FeeWaiverOrReimbursementOverAssetsDateOfTermination>
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        <link:footnote id="fn1_" xlink:label="fn1_" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-size:7.0pt; font-family:Sans-Serif; font-style:normal; font-weight:normal; text-decoration:none;">
The fees and expenses shown in the table and included in the example below reflect the fees and expenses
of both the Fund and The U.S. Government Money Market Portfolio (Master Portfolio), in which the Fund
seeks to invest all of its assets in order to pursue its investment goal.</xhtml:span></link:footnote>
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          xlink:from="_36_"
          xlink:to="fn1_"
          xlink:type="arc"/>
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          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_37_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_38_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_35_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_47_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_41_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_50_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_40_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_48_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_39_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_49_"
          xlink:to="fn1_"
          xlink:type="arc"/>
        <link:footnoteArc
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          xlink:from="_42_"
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          xlink:type="arc"/>
        <link:loc xlink:href="#_46_" xlink:label="_46_" xlink:type="locator"/>
        <link:loc xlink:href="#_44_" xlink:label="_44_" xlink:type="locator"/>
        <link:loc xlink:href="#_45_" xlink:label="_45_" xlink:type="locator"/>
        <link:loc xlink:href="#_43_" xlink:label="_43_" xlink:type="locator"/>
        <link:footnote id="fn2_" xlink:label="fn2_" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-size:7.0pt; font-family:Sans-Serif; font-style:normal; font-weight:normal; text-decoration:none;">
Transfer agency fees on Class R6 shares of the Fund have been capped so that transfer agency fees for
that class do not exceed 0.02% until October 31, 2024. During its term, this fee agreement may not be
terminated or amended without approval of the board of trustees except to add series and classes, to
reflect the extension of termination dates or to lower the waiver and expense limitation (which would
result in lower fees for shareholders).</xhtml:span></link:footnote>
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          xlink:from="_46_"
          xlink:to="fn2_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_44_"
          xlink:to="fn2_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_45_"
          xlink:to="fn2_"
          xlink:type="arc"/>
        <link:footnoteArc
          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_43_"
          xlink:to="fn2_"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#_119_"
          xlink:label="_119_"
          xlink:type="locator"/>
        <link:loc
          xlink:href="#_121_"
          xlink:label="_121_"
          xlink:type="locator"/>
        <link:footnote id="fn3_" xlink:label="fn3_" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:p style="font-size:7.0pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;">Since inception October 15, 2019.</xhtml:p></link:footnote>
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          xlink:from="_119_"
          xlink:to="fn3_"
          xlink:type="arc"/>
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          xlink:from="_121_"
          xlink:to="fn3_"
          xlink:type="arc"/>
        <link:loc
          xlink:href="#_124_"
          xlink:label="_124_"
          xlink:type="locator"/>
        <link:footnote id="fn4_" xlink:label="fn4_" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:p style="font-size:7.0pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;">Since inception May 1, 2013.</xhtml:p></link:footnote>
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          xlink:from="_124_"
          xlink:to="fn4_"
          xlink:type="arc"/>
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