def removeReader(self, reader):
        """Remove a Selectable for notification of data available to read.
        """
        if reader in self._reads:
            del self._events[self._reads[reader]]
            del self._reads[reader]

            # If the descriptor is closed, move it out of the dictionary of
            # reading descriptors into the dictionary of waiting descriptors.
            if reader in self._closedAndReading:
                self._closedAndNotReading[reader] = True
                del self._closedAndReading[reader]
Remove a Selectable for notification of data available to read.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/win32eventreactor.py