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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 delete(self):
 """Deletes the current curve. :raises RuntimeError: Raises when` when one tries to delete a read-only curve. """

        if self._writeable:
            self._write(('CRVDEL', Integer), self.idx)
        else:
            raise RuntimeError('Can not delete read-only curves.')