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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 _check_image(self, image_nD):
 """Sanity checks on the image data"""


        self.input_image = load_image_from_disk(image_nD)

        if len(self.input_image.shape) < 3:
            raise ValueError('Input image must be atleast 3D')

        if np.count_nonzero(self.input_image) == 0:
            raise ValueError('Input image is completely filled with zeros! '
                             'Must be non-empty')