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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 log(self, statement):
        '''Write statement to stderr with timing info in DEBUG mode.'''
        global DEBUG
        time_ms = 1000 * time.time()
        if DEBUG:
            total_time_ms = time_ms - self._start_time_ms_
            lap_time_ms = time_ms - self._last_time_ms_
            sys.stderr.write('%6.f (%6.f ms) %s\n' % (
                total_time_ms, lap_time_ms, statement))
        self._last_time_ms_ = time_ms