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   &lt;!-- Begin Block Tagged Note 3 - us-gaap:LongTermDebtTextBlock--&gt;
   &lt;div style="font-family: 'Times New Roman',Times,serif"&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;&lt;b&gt;3. Long-Term Debt&lt;/b&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;As of June&amp;#160;30, 2010 and December&amp;#160;31, 2009, the Company&amp;#8217;s long-term debt was as follows:
   &lt;/div&gt;
   &lt;div align="center"&gt;
   &lt;table style="font-size: 10pt; text-align: left" cellspacing="0" border="0" cellpadding="0" width="100%"&gt;
   &lt;!-- Begin Table Head --&gt;
   &lt;tr valign="bottom"&gt;
       &lt;td width="76%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 8pt" valign="bottom"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="center" colspan="2"&gt;&lt;b&gt;June 30,&lt;/b&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="center" colspan="2"&gt;&lt;b&gt;December 31,&lt;/b&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 8pt" valign="bottom"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"&gt;&lt;b&gt;2010&lt;/b&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"&gt;&lt;b&gt;2009&lt;/b&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 8pt" valign="bottom"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="center" colspan="6"&gt;&lt;b&gt;(In thousands)&lt;/b&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;!-- End Table Head --&gt;
   &lt;!-- Begin Table Body --&gt;
   &lt;tr valign="bottom" style="background: #cceeff"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Bank credit facility
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="left"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;568,000&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="left"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;305,000&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;7 &lt;sup style="font-size: 85%; vertical-align: text-top"&gt;1&lt;/sup&gt;/&lt;sub style="font-size: 85%; vertical-align: text-bottom"&gt;2&lt;/sub&gt;% Senior Notes, due April&amp;#160;15, 2013, net of discount
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;298,410&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;298,125&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom" style="background: #cceeff"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;8% Senior Notes, due May&amp;#160;15, 2017
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;300,000&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;300,000&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;11 &lt;sup style="font-size: 85%; vertical-align: text-top"&gt;3&lt;/sup&gt;/&lt;sub style="font-size: 85%; vertical-align: text-bottom"&gt;4&lt;/sub&gt;% Senior Notes, due June&amp;#160;30, 2016, net of discount
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;292,154&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;291,725&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 1px"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;&amp;#160;
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom" style="background: #cceeff"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Total long-term debt
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="left"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;1,458,564&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="left"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;1,194,850&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 1px"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;&amp;#160;
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
           &lt;td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
           &lt;td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;!-- End Table Body --&gt;
   &lt;/table&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&lt;i&gt;Bank Credit Facility &amp;#8212; &lt;/i&gt;The Company has a secured revolving credit facility with a group of
   banks pursuant to an amended and restated credit agreement dated March&amp;#160;2, 2006, as further amended.
   The credit facility matures January&amp;#160;31, 2012 and is subject to a borrowing base which is
   redetermined periodically. The outstanding principal balance of loans under the credit facility may
   not exceed the borrowing base. The most recent borrowing base redetermination concluded in April
   2010 when the credit facility was amended to:
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt"&gt;
   &lt;table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; text-align: left"&gt;
   &lt;tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"&gt;
       &lt;td width="1%" style="background: transparent"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%" nowrap="nowrap" align="left"&gt;&lt;b&gt;&amp;#8226;&lt;/b&gt;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;Increase the borrowing base by $150.0&amp;#160;million to $950.0&amp;#160;million until the next
   redetermination under the credit agreement,&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr&gt;
       &lt;td style="font-size: 6pt"&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"&gt;
       &lt;td width="1%" style="background: transparent"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%" nowrap="nowrap" align="left"&gt;&lt;b&gt;&amp;#8226;&lt;/b&gt;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;Reschedule the regular periodic borrowing base redeterminations to begin in February
   and August of each year,&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr&gt;
       &lt;td style="font-size: 6pt"&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"&gt;
       &lt;td width="1%" style="background: transparent"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%" nowrap="nowrap" align="left"&gt;&lt;b&gt;&amp;#8226;&lt;/b&gt;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;Give the lenders an option to redetermine the borrowing base upon termination of hedge
   contracts with more than six months remaining in their original nominal term,&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr&gt;
       &lt;td style="font-size: 6pt"&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"&gt;
       &lt;td width="1%" style="background: transparent"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%" nowrap="nowrap" align="left"&gt;&lt;b&gt;&amp;#8226;&lt;/b&gt;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;Increase the maximum permitted ratio of total debt to EBITDA (as defined in the credit
   agreement) to 3.5 to 1.0 from 2.5 to 1.0, and&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr&gt;
       &lt;td style="font-size: 6pt"&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"&gt;
       &lt;td width="1%" style="background: transparent"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%" nowrap="nowrap" align="left"&gt;&lt;b&gt;&amp;#8226;&lt;/b&gt;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;Give Mariner optionality to issue before January&amp;#160;1, 2011 up to $400.0&amp;#160;million in
   additional unsecured debt with a non-default interest rate of up to 13% per annum (plus a
   maximum default rate of 3%) and a scheduled maturity date no earlier than March&amp;#160;2, 2015.
   Upon closing such a debt issuance, the borrowing base automatically would reduce by 25% of
   the aggregate principal amount of the debt issued until otherwise redetermined under the
   credit agreement.&lt;/td&gt;
   &lt;/tr&gt;
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   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;As of June&amp;#160;30, 2010, maximum credit availability under the facility was $1.0&amp;#160;billion,
   including up to $50.0&amp;#160;million in letters of credit, subject to a borrowing base of $950.0&amp;#160;million.
   As of June&amp;#160;30, 2010, there were $568.0&amp;#160;million in advances outstanding under the credit facility
   and four letters of credit outstanding totaling $4.7&amp;#160;million, of which $4.2&amp;#160;million is required for
   plugging and abandonment obligations at certain of the Company&amp;#8217;s offshore fields. As of June&amp;#160;30,
   2010, after accounting for the $4.7&amp;#160;million of letters of credit, the Company had $377.3&amp;#160;million
   available to borrow under the credit facility.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Borrowings under the bank credit facility bear interest at either a LIBOR-based rate or a
   prime-based rate, at the Company&amp;#8217;s option, plus a specified margin. At June&amp;#160;30, 2010, when
   borrowings at both LIBOR and prime-based rates were outstanding, the blended interest rate was
   2.92% on all amounts borrowed. During the six months ended June&amp;#160;30, 2010, the commitment fee on
   unused capacity was 0.5% per annum. Commitment fees are included in &amp;#8220;Accrued interest&amp;#8221; in the
   Condensed Consolidated Balance Sheets in Item&amp;#160;1 of Part&amp;#160;I of this Quarterly Report.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The credit facility subjects the Company to various restrictive covenants and contains other
   usual and customary terms and conditions, including limits on additional debt, cash dividends and
   other restricted payments, liens, investments, asset dispositions, mergers and speculative hedging.
   Financial covenants under the credit facility require the Company to, among other things:
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt"&gt;
   &lt;table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; text-align: left"&gt;
   &lt;tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"&gt;
       &lt;td width="1%" style="background: transparent"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%" nowrap="nowrap" align="left"&gt;&lt;b&gt;&amp;#8226;&lt;/b&gt;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;maintain a ratio of consolidated current assets plus the unused borrowing base to
   consolidated current liabilities of not less than 1.0 to 1.0; and&lt;/td&gt;
   &lt;/tr&gt;
   &lt;/table&gt;
   &lt;/div&gt;
   &lt;!-- Folio --&gt;
   &lt;!-- /Folio --&gt;
   &lt;/div&gt;
   &lt;!-- PAGEBREAK --&gt;
   &lt;div style="font-family: 'Times New Roman',Times,serif"&gt;
   &lt;div style="margin-top: 6pt"&gt;
   &lt;table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; text-align: left"&gt;
   &lt;tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"&gt;
       &lt;td width="1%" style="background: transparent"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%" nowrap="nowrap" align="left"&gt;&lt;b&gt;&amp;#8226;&lt;/b&gt;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;maintain a ratio of total debt to EBITDA (as defined in the credit agreement) of not
   more than 3.5 to 1.0.&lt;/td&gt;
   &lt;/tr&gt;
   &lt;/table&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The Company was in compliance with these covenants as of June&amp;#160;30, 2010 when the ratio of
   consolidated current assets plus the unused borrowing base to consolidated current liabilities was
   1.92 to 1.0 and the ratio of total debt to EBITDA was 2.6 to 1.0.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The Company&amp;#8217;s payment and performance of its obligations under the credit facility (including
   any obligations under commodity and interest rate hedges entered into with facility lenders) are
   secured by liens upon substantially all of the assets of the Company and its subsidiaries, except
   its Canadian subsidiary, and guaranteed by its subsidiaries, other than Mariner Energy Resources,
   Inc. which is a co-borrower, and its Canadian subsidiary.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&lt;i&gt;Senior Notes &amp;#8212; &lt;/i&gt;In 2009, the Company sold and issued $300.0&amp;#160;million aggregate principal amount
   of its 11&lt;sup style="font-size: 85%; vertical-align: text-top"&gt;3&lt;/sup&gt;/&lt;sub style="font-size: 85%; vertical-align: text-bottom"&gt;4&lt;/sub&gt;% senior notes due 2016 (the &amp;#8220;11&lt;sup style="font-size: 85%; vertical-align: text-top"&gt;3&lt;/sup&gt;/&lt;sub style="font-size: 85%; vertical-align: text-bottom"&gt;4&lt;/sub&gt;%
   Notes&amp;#8221;). In 2007, the Company sold and issued $300.0&amp;#160;million aggregate principal amount of its 8%
   senior notes due 2017 (the &amp;#8220;8% Notes&amp;#8221;). In 2006, the Company sold and issued $300.0&amp;#160;million
   aggregate principal amount of its 7&lt;sup style="font-size: 85%; vertical-align: text-top"&gt;1&lt;/sup&gt;/&lt;sub style="font-size: 85%; vertical-align: text-bottom"&gt;2&lt;/sub&gt;% senior notes due 2013 (the
   &amp;#8220;7&lt;sup style="font-size: 85%; vertical-align: text-top"&gt;1&lt;/sup&gt;/&lt;sub style="font-size: 85%; vertical-align: text-bottom"&gt;2&lt;/sub&gt;% Notes&amp;#8221; and together with the 11&lt;sup style="font-size: 85%; vertical-align: text-top"&gt;3&lt;/sup&gt;/&lt;sub style="font-size: 85%; vertical-align: text-bottom"&gt;4&lt;/sub&gt;% Notes and
   the 8% Notes, the &amp;#8220;Notes&amp;#8221;). The Notes are governed by indentures that are substantially identical
   for each series. The Notes are senior unsecured obligations of the Company. The
   11&lt;sup style="font-size: 85%; vertical-align: text-top"&gt;3&lt;/sup&gt;/&lt;sub style="font-size: 85%; vertical-align: text-bottom"&gt;4&lt;/sub&gt;% Notes mature on June&amp;#160;30, 2016 with interest payable on June&amp;#160;30 and
   December&amp;#160;30 of each year beginning December&amp;#160;30, 2009. The 8% Notes mature on May&amp;#160;15, 2017 with
   interest payable on May&amp;#160;15 and November&amp;#160;15 of each year. The 7&lt;sup style="font-size: 85%; vertical-align: text-top"&gt;1&lt;/sup&gt;/&lt;sub style="font-size: 85%; vertical-align: text-bottom"&gt;2&lt;/sub&gt;% Notes
   mature on April&amp;#160;15, 2013 with interest payable on April&amp;#160;15 and October&amp;#160;15 of each year. There is no
   sinking fund for the Notes. The Company and its restricted subsidiaries are subject to certain
   financial and non-financial covenants under each of the indentures governing the Notes. The Company
   was in compliance with the financial covenants under the Notes as of June&amp;#160;30, 2010.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&lt;i&gt;Capitalized Interest &amp;#8212; &lt;/i&gt;For the three-month periods ended June&amp;#160;30, 2010 and 2009, capitalized
   interest totaled $6.2&amp;#160;million and $3.0&amp;#160;million, respectively. For the six-month periods ended June
   30, 2010 and 2009, capitalized interest totaled $11.5&amp;#160;million and $5.2&amp;#160;million, respectively.
   &lt;/div&gt;
   &lt;/div&gt;
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 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 02
 -Paragraph 22
 -Article 5

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