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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 query_paths(self):
 """ RETURN A LIST OF ALL NESTED COLUMNS """

        output = self.namespace.alias_to_query_paths.get(self.name)
        if output:
            return output
        Log.error("Can not find index {{index|quote}}", index=self.name)