Identification with zero disclosure is not n = p * q?

The crux of the matter is that you need to identify two sides A and B according to the Protocol zero-knowledge. Was thinking of using either the Protocol of Fiat - Shamir, or Gill - of Kiskutya. But there is n = p * q, where p and q are simple. It is not very convenient, you need to identify for any sequence of numbers and letters.
If you use a designated two algorithms, how best to convert a numeric letter sequence in numerical and then how to obtain a Prime number? use Python, if someone tyknet nose in the library, will be quite good.

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