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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 _progressbar(self, msg, iter_num):
 """Display a progress bar with current loss. Parameters msg : str Message to print alongside the progress bar iter_num : int Iteration number. Progress is only printed if this is a multiple of `self.display_progress`. """

        if self.display_progress and \
                                (iter_num + 1) % self.display_progress == 0:
            sys.stderr.write('\r')
            sys.stderr.write("Iteration {}: {}".format(iter_num + 1, msg))
            sys.stderr.flush()