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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 between(start, delta, end=None):
 """Return an iterator between this date till given end point. Example usage: 2008/05/12 11:45 2008/05/12 11:45 2008/05/13 11:45 2008/05/14 11:45 2008/05/15 11:45 2008/05/16 11:45 Args: start: The date to start at. delta: The interval to iterate with. end: (Optional) Date to end at. If not given the iterator will never terminate. Yields: datetime_tz objects. """

    toyield = start
    while end is None or toyield < end:
      yield toyield
      toyield += delta