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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 account_unblock(self, id):
 """ Unblock a user. Returns a `relationship dict`_ containing the updated relationship to the user. """

        id = self.__unpack_id(id)
        url = '/api/v1/accounts/{0}/unblock'.format(str(id))
        return self.__api_request('POST', url)