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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 clear(self):
 """Delete the history."""

        self.sampler.clear()
        self.samples_list = self._comm.gather(self.sampler.samples, root=0)
        if hasattr(self.sampler, 'weights'):
            self.weights_list = self._comm.gather(self.sampler.weights, root=0)
        else:
            self.weights_list = None