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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 link_user_account(self, user_id, body):
 """Link user accounts. Links the account specified in the body (secondary account) to the account specified by the id param of the URL (primary account). Args: id (str):
 The user_id of the primary identity where you are linking the secondary account to. body (dict):
 Please see: https://auth0.com/docs/api/v2#!/Users/post_identities """

        url = self._url('{}/identities'.format(user_id))
        return self.client.post(url, data=body)