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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 _get_affine_transform(self):
 """The affine portion of the base transform. This is called by LambertAxes._set_lim_and_transforms."""

        # How big is the projected globe?
        # In the case of a stereonet, it's actually constant.
        xscale = yscale = self._scale
        # Create an affine transform to stretch the projection from 0-1
        return Affine2D() \
            .rotate(np.radians(self.rotation)) \
            .scale(0.5 / xscale, 0.5 / yscale) \
            .translate(0.5, 0.5)