parameters: (self, key, message)
docstring: Replace the keyed message; raise KeyError if it doesn't exist.
docstring_summary: Replace the keyed message; raise KeyError if it doesn't exist.
docstring_tokens: Replace the keyed message ; raise KeyError if it doesn t exist .
function: def __setitem__(self, key, message):
          """Replace the keyed message; raise KeyError if it doesn't exist."""
          self._lookup(key)
          self._toc[key] = self._append_message(message)
          self._pending = True
function_tokens: def __setitem__ ( self , key , message ) : self . _lookup ( key ) self . _toc [ key ] = self . _append_message ( message ) self . _pending = True