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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 _is_under_root(self, full_path):
 """Guard against arbitrary file retrieval."""

        if (path.abspath(full_path) + path.sep)\
                .startswith(path.abspath(self.root) + path.sep):
            return True
        else:
            return False