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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 calculate_progress(self, scan_id):
 """ Calculate the total scan progress from the partial target progress. """


        t_prog = dict()
        for target in self.get_scan_target(scan_id):
            t_prog[target] = self.get_scan_target_progress(scan_id, target)
        return sum(t_prog.values())/len(t_prog)