def A1(self, algorithm, auth_pass):

        username = self.params["username"]
        if algorithm == 'MD5' or not algorithm:
            return "%s:%s:%s" % (username, self.realm, auth_pass)
        elif algorithm == 'MD5-Sess':
            return self.apply_checksum('%s:%s:%s:%s:%s' % \
                                       (username,
                                       self.realm,
                                       auth_pass,
                                       self.params['nonce'],
                                       self.params['cnonce']))
If 'algorithm' is "MD5" or unset, A1 is:
dataset/ETHPy150Open gmr/tinman/tinman/auth/digest.py/DigestAuthMixin.A1