def in_subclip(self, start_time=None, end_time=None):
        """Returns a sequence of [(t1,t2), text] covering all the given subclip
        from start_time to end_time. The first and last times will be cropped so as
        to be exactly start_time and end_time if possible.
        """

        def is_in_subclip(t1, t2):
            try:
                return (start_time <= t1 < end_time) or (start_time < t2 <= end_time)
            except Exception:
                return False

        def try_cropping(t1, t2):
            try:
                return max(t1, start_time), min(t2, end_time)
            except Exception:
                return t1, t2

        return [
            (try_cropping(t1, t2), txt)
            for ((t1, t2), txt) in self.subtitles
            if is_in_subclip(t1, t2)
        ]
Returns a sequence of [(t1,t2), text] covering all the given subclip
        from start_time to end_time. The first and last times will be cropped so as
        to be exactly start_time and end_time if possible.
        
moviepy/video/tools/subtitles.py