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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 command_max_run_time(self, event=None):
 """ CPU burst max running time - self.runtime_cfg.max_run_time """

        try:
            max_run_time = self.max_run_time_var.get()
        except ValueError:
            max_run_time = self.runtime_cfg.max_run_time

        self.runtime_cfg.max_run_time = max_run_time
        self.max_run_time_var.set(self.runtime_cfg.max_run_time)