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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 create(cls, user_id, client_id, extra_data):
 """Create new remote account for user. :param user_id: User id. :param client_id: Client id. :param extra_data: JSON-serializable dictionary of any extra data that needs to be save together with this link. :returns: A :class:`invenio_oauthclient.models.RemoteAccount` instance. """

        with db.session.begin_nested():
            account = cls(
                user_id=user_id,
                client_id=client_id,
                extra_data=extra_data or dict()
            )
            db.session.add(account)
        return account