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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 _notify_bucket(self, real_time):
 """ Internal helper. This 'does' the callbacks in a particular bucket. :param real_time: the bucket to do callbacks on """

        (delayed_call, calls) = self._buckets[real_time]
        del self._buckets[real_time]
        errors = []

        def notify_one_chunk(calls, chunk_size, chunk_delay_ms):
            for call in calls[:chunk_size]:
                try:
                    call()
                except Exception as e:
                    errors.append(e)
            calls = calls[chunk_size:]
            if calls:
                self._create_delayed_call(
                    chunk_delay_ms / 1000.0,
                    notify_one_chunk, calls, chunk_size, chunk_delay_ms,
                )
            else:
                # done all calls; make sure there were no errors
                if len(errors):
                    msg = u"Error(s) processing call_later bucket:\n"
                    for e in errors:
                        msg += u"{}\n".format(e)
                    raise RuntimeError(msg)
        # ceil()ing because we want the number of chunks, and a
        # partial chunk is still a chunk
        delay_ms = self._bucket_milliseconds / math.ceil(float(len(calls)) / self._chunk_size)
        # I can't imagine any scenario in which chunk_delay_ms is
        # actually less than zero, but just being safe here
        notify_one_chunk(calls, self._chunk_size, max(0.0, delay_ms))