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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 write_case_data(self, file):

 """ Writes case data to file.
 """

        change_code = 0
        s_base = self.case.base_mva
        timestr = time.strftime("%Y%m%d%H%M", time.gmtime())
        file.write("%d, %8.2f, 30 / PSS(tm)E-30 RAW created by Pylon (%s).\n" %
                   (change_code, s_base, timestr))
        file.write("Modified by Hantao Cui, CURENT, UTK\n ")
        file.write("%s, %d BUSES, %d BRANCHES\n" %
                   (self.case.name, len(self.case.buses), len(self.case.branches)))