<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _closeCompletion(self):
 """Close completion, if visible. Delete widget """

        if self._widget is not None:
            self._widget.close()
            self._widget = None
            self._completionOpenedManually = False