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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 _calc_sizes(self):
 """Package size calculation """

        if self.size > 1024:
            self.unit = "Mb"
            self.size = (self.size / 1024)
        if self.size > 1024:
            self.unit = "Gb"
            self.size = (self.size / 1024)