def __getitem__(self, pos):
        if pos not in self._content:
            widget = self._load_widget(pos)
            if widget is None:
                raise IndexError
            self._content[pos] = widget
        return self._content[pos]
dataset/ETHPy150Open kdart/pycopia/QA/pycopia/QA/tui/walkers.py/CachingTreeWalker.__getitem__/original