timezone.py 文件源码

def _find_utc_index(self, dt):
        lo, hi = 0, len(self._utc_transition_times)
        hint = self._local_hint.get('_utc')
        if hint:
            if dt == hint[0]:
                return hint[1]
            elif dt < hint[0]:
                hi = hint[1] + 1
            else:
                lo = hint[1]

        idx = max(0, bisect_right(self._utc_transition_times, dt, lo, hi) - 1)

        self._local_hint['_utc'] = (dt, idx)

        return idx