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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 split(self, point=None):
 """ Split this sequence into two halves and return them. The original sequence remains unmodified. :param point: defines the split point, if None then the centre is used :return: two Sequence objects -- one for each side """

    if point is None:
      point = len(self) / 2

    r1 = Sequence(self.name + ".1", self.sequenceData[:point])
    r2 = Sequence(self.name + ".2", self.sequenceData[point:])

    return r1, r2