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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 visit_Return(self, node):
 """ Compute return type and merges with others possible return type."""

        self.generic_visit(node)
        # No merge are done if the function is a generator.
        if not self.yield_points:
            assert node.value, "Values were added in each return statement."
            self.combine(self.current, node.value)