Operating leases - Schedule of Components of Lease Cost (Details) - CNY (¥)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule of Component of Lease Cost Abstract
Operating lease cost	¥ 11,385,312	¥ 3,277,780	¥ 389,799
Short-term lease cost	295,564	1,867,850	48,000
Total lease cost	¥ 11,680,876	¥ 5,145,630	¥ 437,799

Schedule of component of lease cost abstract.

No definition available.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980

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+ Details

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI https://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

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-Publisher FASB
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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980

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