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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 last_update_time(self) -> float: """The last time at which the report was modified."""

        stdout = self.stdout_interceptor
        stderr = self.stderr_interceptor

        return max([
            self._last_update_time,
            stdout.last_write_time if stdout else 0,
            stderr.last_write_time if stderr else 0,
        ])