code: def digest_auth_user(self, realm, user_name, environ):
          
          user = self._get_realm_entry(realm, user_name)
          if user is None:
              return False
          password = user.get("password")
          environ["wsgidav.auth.roles"] = user.get("roles", [])
          return self._compute_http_digest_a1(realm, user_name, password)
docs: Computes digest hash A1 part.