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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_Call(self, node):
 """ Function call depend on all function use in the call. >> a = foo(bar(c) or foobar(d)) Return type depend on [foo, bar] or [foo, foobar] """

        args = [self.visit(arg) for arg in node.args]
        func = self.visit(node.func)
        params = args + [func or []]
        return list({frozenset.union(*p) for p in itertools.product(*params)})