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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def jwt_is_expired(self, access_token=None, leeway=0):
 """Validate JWT access token expiration. Args: access_token (str):
 Access token to validate. Defaults to ``None``. leeway (float):
 Time in seconds to adjust for local clock skew. Defaults to 0. Returns: bool: ``True`` if expired, otherwise ``False``. """

        if access_token is not None:
            exp = self._decode_exp(access_token)
        else:
            exp = self.jwt_exp
        now = time()
        if exp < (now - leeway):
            return True
        return False