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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 set_signal(self, signal, name):
 r"""Attach a signal to the graph. Attached signals can be accessed (and modified or deleted) through the :attr:`signals` dictionary. Parameters signal : array_like A sequence that assigns a value to each vertex. The value of the signal at vertex `i` is ``signal[i]``. name : String Name of the signal used as a key in the :attr:`signals` dictionary. Examples -------- {'mysignal': array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])} """

        signal = self._check_signal(signal)
        self.signals[name] = signal