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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 sign_encrypt(self, session_info, client_id, code=None, access_token=None, user_info=None, sign=True, encrypt=False, extra_claims=None):
 """ Signed and or encrypt a IDToken :param session_info: Session information :param client_id: Client ID :param code: Access grant :param access_token: Access Token :param user_info: User information :param sign: If the JWT should be signed :param encrypt: If the JWT should be encrypted :param extra_claims: Extra claims to be added to the ID Token :return: IDToken as a signed and/or encrypted JWT """


        _cntx = self.endpoint_context

        client_info = _cntx.cdb[client_id]
        alg_dict = get_sign_and_encrypt_algorithms(_cntx, client_info,
                                                   'id_token', sign=sign,
                                                   encrypt=encrypt)

        _authn_event = session_info['authn_event']

        _idt_info = self.payload(session_info,
                                 acr=_authn_event["authn_info"],
                                 alg=alg_dict['sign_alg'], code=code,
                                 access_token=access_token, user_info=user_info,
                                 auth_time=_authn_event["authn_time"],
                                 extra_claims=extra_claims)

        _jwt = JWT(_cntx.keyjar, iss=_cntx.issuer,
                   lifetime=_idt_info['lifetime'], **alg_dict)

        return _jwt.pack(_idt_info['payload'], recv=client_id)