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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 close(self):
 """Close method. Closes the underlying comm. When the comm is closed, all of the widget views are automatically removed from the front-end."""

        if self.comm is not None:
            Widget.widgets.pop(self.model_id, None)
            self.comm.close()
            self.comm = None
            self._ipython_display_ = None