As I found out, 2a shadow hash keys are deprecated because 2a has implementation flaws. It was fixed in 2011, and now 2y hits are widely used on Linux systems.
I tried to find a Python library that computes 2y hash, but I failed. I searched for at least two hours and looked through all available libraries, but each individual library for Python only calculates 2a hashes. Most of them are a shell for the bcrypt link from BSD, but they only compute 2a -hashes.
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