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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 unlink_user_account(self, id, provider, user_id):
 """Unlink a user account Args: id (str):
 The user_id of the user identity. provider (str):
 The type of identity provider (e.g: facebook). user_id (str):
 The unique identifier for the user for the identity. See: https://auth0.com/docs/api/management/v2#!/Users/delete_user_identity_by_user_id """

        url = self._url('{}/identities/{}/{}'.format(id, provider, user_id))
        return self.client.delete(url)