import numpy as np
from photutils.segmentation import SegmentationImage

data = np.array([[1, 1, 0, 0, 4, 4],
                 [0, 0, 0, 0, 0, 4],
                 [0, 0, 3, 3, 0, 0],
                 [7, 0, 0, 0, 0, 5],
                 [7, 7, 0, 5, 5, 5],
                 [7, 7, 0, 0, 5, 5]])
segm = SegmentationImage(data)
segm.imshow(figsize=(5, 5))
segm.plot_patches(edgecolor='white', lw=2)