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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 _merge_expressions(self, other):
 """ Merge the inputs of two NumericalExpressions into a single input tuple, rewriting their respective string expressions to make input names resolve correctly. Returns a tuple of (new_self_expr, new_other_expr, new_inputs) """

        new_inputs = tuple(set(self.inputs).union(other.inputs))
        new_self_expr = self._rebind_variables(new_inputs)
        new_other_expr = other._rebind_variables(new_inputs)
        return new_self_expr, new_other_expr, new_inputs