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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 parse(self, msg, name):
 """Parses the message. We check that the message is properly formatted. :param msg: a json-encoded value containing a JWS or JWE+JWS token :raises InvalidMessage: if the message cannot be parsed or validated :returns: A verified payload """


        try:
            jtok = JWT(jwt=msg)
        except Exception as e:
            raise InvalidMessage('Failed to parse message: %s' % str(e))

        try:
            token = jtok.token
            if isinstance(token, JWE):
                token.decrypt(self.kkstore.server_keys[KEY_USAGE_ENC])
                # If an encrypted payload is received then there must be
                # a nested signed payload to verify the provenance.
                payload = token.payload.decode('utf-8')
                token = JWS()
                token.deserialize(payload)
            elif isinstance(token, JWS):
                pass
            else:
                raise TypeError("Invalid Token type: %s" % type(jtok))

            # Retrieve client keys for later use
            self.client_keys = [
                JWK(**self._get_key(token.jose_header, KEY_USAGE_SIG)),
                JWK(**self._get_key(token.jose_header, KEY_USAGE_ENC))]

            # verify token and get payload
            token.verify(self.client_keys[KEY_USAGE_SIG])
            claims = json_decode(token.payload)
        except Exception as e:
            logger.debug('Failed to validate message', exc_info=True)
            raise InvalidMessage('Failed to validate message: %s' % str(e))

        check_kem_claims(claims, name)
        self.name = name
        self.payload = claims.get('value')
        self.msg_type = 'kem'

        return {'type': self.msg_type,
                'value': {'kid': self.client_keys[KEY_USAGE_ENC].key_id,
                          'claims': claims}}