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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 get_refresh_flag(self, filename):
 """ set refresh data flag return True or False """

        if filename is not None and filename != self.open_filename:
            self.open_filename = filename
            self.tree_refresh_flag = True
            self.data_refresh_flag = True
            return True
        else:
            return False