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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def completion_post_event_input_accelerators(editor, event):
 """ Implements completion post event input accelerators. :param editor: Document editor. :type editor: QWidget :param event: Event being handled. :type event: QEvent :return: Process event. :rtype: bool """


    if editor.completer:
        if editor.completer.popup().isVisible():
            perform_completion(editor)
    return True