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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 _not_empty(self, view, slice_):
 """Checks if the density is too low. """


        img2d = self._get_axis(self._image, view, slice_)
        return (np.count_nonzero(img2d) / img2d.size) > self._min_density