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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 adjacent(labels):
    '''Return a binary mask of all pixels which are adjacent to a pixel of 
       a different label.
       
    '''
    high = labels.max()+1
    if high > np.iinfo(labels.dtype).max:
        labels = labels.astype(np.int)
    image_with_high_background = labels.copy()
    image_with_high_background[labels == 0] = high
    min_label = scind.minimum_filter(image_with_high_background,
                                     footprint=np.ones((3,3),bool),
                                     mode = 'constant',
                                     cval = high)
    max_label = scind.maximum_filter(labels,
                                     footprint=np.ones((3,3),bool),
                                     mode = 'constant',
                                     cval = 0)
    return (min_label != max_label) & (labels > 0)