Returns the SOAP headers required for request authorization.

    Args:
      create_method: The SOAP library specific method used to instantiate SOAP
      objects.

    Returns:
      A SOAP object containing the headers.

def GetSOAPHeaders(self, create_method):
    """Returns the SOAP headers required for request authorization.

    Args:
      create_method: The SOAP library specific method used to instantiate SOAP
      objects.

    Returns:
      A SOAP object containing the headers.
    """
    header = create_method(self._SOAP_HEADER_CLASS)
    header.networkCode = self._ad_manager_client.network_code
    header.applicationName = ''.join([
        self._ad_manager_client.application_name,
        googleads.common.GenerateLibSig(self._PRODUCT_SIG)])
    return header