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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 ChangeScaleFactor(self, newfactor):
 """Changes the zoom of the graph manually. 1.0 is the original canvas size. Args: # float value between 0.0 and 5.0 newfactor: 0.7 """

    if float(newfactor) > 0 and float(newfactor) < self._MAX_ZOOM:
      self._zoomfactor = newfactor