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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 properties(self):
 """Return various properties of the binary tree. :return: Binary tree properties. :rtype: dict **Example**: .. doctest:: 2 5 2 1 5 1 3 True False True False True False True """

        properties = _get_tree_properties(self)
        properties.update({
            'is_bst': _is_bst(self),
            'is_balanced': _is_balanced(self) >= 0
        })
        return properties