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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 _call(self, x, out=None):
 """Calculate partial derivative of ``x``."""

        if out is None:
            out = self.range.element()

        # TODO: this pipes CUDA arrays through NumPy. Write native operator.
        with writable_array(out) as out_arr:
            finite_diff(x.asarray(), axis=self.axis, dx=self.dx,
                        method=self.method, pad_mode=self.pad_mode,
                        pad_const=self.pad_const, out=out_arr)
        return out