<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _render_our_module_key_flags(self, module, output_lines, prefix=''):
 """Returns a help string for the key flags of a given module. Args: module: module|str, the module to render key flags for. output_lines: [str], a list of strings. The generated help message lines will be appended to this list. prefix: str, a string that is prepended to each generated help line. """

    key_flags = self.get_key_flags_for_module(module)
    if key_flags:
      self._render_module_flags(module, key_flags, output_lines, prefix)