v3.21.1

Stock warrants - Additional Information (Details) - Common stock - $ / shares | Nov. 06, 2020 | Jan. 31, 2021 | Jan. 31, 2020
--- | --- | --- | ---
Class of Warrant or Right [Line Items] |  |  |
Number of warrants (in shares) |  | 0 | 75,137
Exercise price (in USD per share) |  |  | $ 8.02
Common stock issued upon the exercise of warrants (in shares) | 60,338 |  |

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