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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 _break_signals(self):
 r"""Break N-dimensional signals into N 1D signals."""

        for name in list(self.signals.keys()):
            if self.signals[name].ndim == 2:
                for i, signal_1d in enumerate(self.signals[name].T):
                    self.signals[name + '_' + str(i)] = signal_1d
                del self.signals[name]