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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 _onCompletionListTabPressed(self):
 """Tab pressed on completion list Insert completable text, if available """

        canCompleteText = self._widget.model().canCompleteText
        if canCompleteText:
            self._qpart.textCursor().insertText(canCompleteText)
            self.invokeCompletionIfAvailable()