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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 the divergence of ``x``."""

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

        ndim = self.range.ndim
        dx = self.range.cell_sides

        tmp = np.empty(out.shape, out.dtype, order=out.space.default_order)
        with writable_array(out) as out_arr:
            for axis in range(ndim):
                finite_diff(x[axis], axis=axis, dx=dx[axis],
                            method=self.method, pad_mode=self.pad_mode,
                            pad_const=self.pad_const,
                            out=tmp)
                if axis == 0:
                    out_arr[:] = tmp
                else:
                    out_arr += tmp

        return out