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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 validate_user_name(self, user_name, timeout=-1):
 """ Verifies if a userName is already in use. Args: user_name: The userName to be verified. timeout: Timeout in seconds. Wait for task completion by default. The timeout does not abort the operation in OneView, just stops waiting for its completion. Returns: True if user name is in use, False if it is not. """

        uri = self.URI + '/validateLoginName/' + user_name
        return self._client.create_with_zero_body(uri=uri, timeout=timeout)