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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):
 r"""Derivative of this operator in ``point``. ``NormOperator().derivative(y)(x) == (y / y.norm()).inner(x)`` This is only applicable in inner product spaces. Parameters point : `domain` `element-like` Point in which to take the derivative. Returns ------- derivative : `InnerProductOperator` Raises ------ ValueError If ``point.norm() == 0``, in which case the derivative is not well defined in the Frechet sense. Notes ----- The derivative cannot be written in a general sense except in Hilbert spaces, in which case it is given by .. math:: (D \|\cdot\|)(y)(x) = \langle y / \|y\|, x \rangle Examples -------- 1.0 """

        point = self.domain.element(point)
        norm = point.norm()
        if norm == 0:
            raise ValueError('not differentiable in 0')

        return InnerProductOperator(point / norm)