code: def GetStructFormatString(self):
      
      if self._data_type_definition.format == definitions.FORMAT_UNSIGNED:
        return self._FORMAT_STRINGS_UNSIGNED.get(
            self._data_type_definition.size, None)
  
      return self._FORMAT_STRINGS_SIGNED.get(
          self._data_type_definition.size, None)
docs: Retrieves the Python struct format string.
  
      Returns:
        str: format string as used by Python struct or None if format string
            cannot be determined.