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

        newnode = nodes.ExtSlice(parent=parent)
        newnode.postinit([self.visit(dim, newnode) for dim in node.dims])
        return newnode