code: def module_getmtime(filename):
      
      if os.path.splitext(filename)[1].lower() in (".pyc", ".pyo") and os.path.exists(filename[:-1]):
          return os.path.getmtime(filename[:-1])
      if os.path.exists(filename):
          return os.path.getmtime(filename)
      return None
docs: Get the mtime associated with a module.  If this is a .pyc or .pyo file and
      a corresponding .py file exists, the time of the .py file is returned.
  
      :param filename: filename of the module.
      :returns: mtime or None if the file doesn"t exist.