PREPAYMENTS AND OTHER CURRENT ASSETS, NET (Details)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2018 CNY (¥)
PREPAYMENTS AND OTHER CURRENT ASSETS, NET
Employee advances	$ 236,749	¥ 1,648,197	¥ 2,158,987
Prepayments and deposits	213,804	1,488,463	693,111
Input VAT recoverable	207,087	1,441,700	1,448,075
Refundable withholding tax	186,305	1,297,016
Other receivables, net of allowance for doubtful accounts of RMB 20,770,928 and RMB 5,343,427 as of December 31, 2018 and 2019, respectively	427,067	2,973,158	1,848,614
Prepayments and other current assets, total	$ 1,271,012	8,848,534	6,148,787
Other receivables, allowance for doubtful accounts		¥ 5,343,427	¥ 20,770,928

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"Carrying amount as of the balance sheet date of refundable withholding tax. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer."

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Amount of valuation allowance for receivables classified as other, due within one year or the normal operating cycle, if longer.

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Amounts due from an Entity employee, not to include stockholders or officers, which are usually due within 1 year (or 1 business cycle).

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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Carrying amount as of the balance sheet date of value added taxes due either from customers arising from sales on credit terms, or as previously overpaid to tax authorities. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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