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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 ToDeltas(self):
 """Convert the sequence to the sequence of differences between points. The value of each point v[i] is replaced by v[i+1] - v[i], except for the last point which is dropped. """

    if len(self.data) < 2:
      self.data = []
      return
    for i in range(0, len(self.data) - 1):
      if self.data[i][0] is None or self.data[i + 1][0] is None:
        self.data[i][0] = None
      else:
        self.data[i][0] = self.data[i + 1][0] - self.data[i][0]
    del self.data[-1]