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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 _dispatch(self, tree):
        "_dispatcher function, _dispatching tree type T to method _T."
        if isinstance(tree, list):
            for t in tree:
                self._dispatch(t)
            return
        meth = getattr(self, "_"+tree.__class__.__name__)
        if tree.__class__.__name__ == 'NoneType' and not self._do_indent:
            return
        meth(tree)