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U. S. GOVERNMENT SECURITIES (Tables) | 12 Months Ended
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Jan. 31, 2021
U. S. GOVERNMENT SECURITIES |
Schedule of U.S. government securities classified as held-to-maturity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | 2021 | ​ | 2020 |
​ | ​ | Carrying | ​ |  | ​ | ​ | Carrying | ​ |  | ​ |
​ |  | Value |  | Fair Value |  | Value |  | Fair Value |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Due within one year | ​ | $ | 9,906,669 | ​ | $ | 9,906,847 | ​ | $ | 13,332,474 | ​ | $ | 13,337,529 | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Due after one year | ​ |  | — | ​ |  | — | ​ |  | — | ​ |  | — | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | $ | 9,906,669 | ​ | $ | 9,906,847 | ​ | $ | 13,332,474 | ​ | $ | 13,337,529 | ​

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