Password Hash Validation (Posting On Python-List Prohibited)

I am writing code to validate entered user passwords against hashes
served up from /etc/shadow via LDAP. I had previously used passlib
<https://passlib.readthedocs.io> to do the hashing. But now I discover
it is not keeping up; for example, Debian and other distros are now
using yescrypt (hashes with “$y$” prefix), but passlib has no support
for that.

However, one language that does seem able to keep up to date is Perl.
So here’s my current password validation function:

    def validate_password(password, hash) :
        "hashes password using the algorithm and salt prefix from hash, and" \
        " returns whether the result matches hash."
        outhash = subprocess.check_output \
          (
            args = ("perl", "-e", "print crypt($ENV{\"PW\"}, $ENV{\"HASH\"});"),
            env = {"PW" : password, "HASH" : hash},
            text = True
          ).strip()
        return \
            outhash == hash
    #end validate_password