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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 in_tree(self, cmd_args):
 """ if a command is in the tree """

        if not cmd_args:
            return True
        tree = self
        try:
            for datum in cmd_args:
                tree = tree.get_child(datum)
        except ValueError:
            return False
        return True