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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 derivative(self, point):
 """Derivative of this operator, always zero. Returns ------- derivative : `ZeroOperator` Examples -------- rn(3).element([ 0., 0., 0.]) """

        return ZeroOperator(domain=self.domain, range=self.range)