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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_exec(self, node, parent):
 """visit an Exec node by returning a fresh instance of it"""

        newnode = nodes.Exec(node.lineno, node.col_offset, parent)
        newnode.postinit(
            self.visit(node.body, newnode),
            _visit_or_none(node, "globals", self, newnode),
            _visit_or_none(node, "locals", self, newnode),
        )
        return newnode