code: def _get_help_for_modules(self, modules, prefix, include_special_flags):
      
      output_lines = []
      for module in modules:
        self._render_our_module_flags(module, output_lines, prefix)
      if include_special_flags:
        self._render_module_flags(
            'absl.flags',
            six.itervalues(_helpers.SPECIAL_FLAGS._flags()),  # pylint: disable=protected-access
            output_lines,
            prefix)
      return '\n'.join(output_lines)
docs: Returns the help string for a list of modules.
  
      Private to absl.flags package.
  
      Args:
        modules: List[str], a list of modules to get the help string for.
        prefix: str, a string that is prepended to each generated help line.
        include_special_flags: bool, whether to include description of
          SPECIAL_FLAGS, i.e. --flagfile and --undefok.