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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_shape_mask(self, shape_obj):
 """ Return full mask where True marks pixels within the given shape. """

        wd, ht = self.get_size()
        yi = np.mgrid[:ht].reshape(-1, 1)
        xi = np.mgrid[:wd].reshape(1, -1)
        pts = np.asarray((xi, yi)).T
        contains = shape_obj.contains_pts(pts)
        return contains