edge tracking by hysteresis python

bottom_to_top = image.copy()
 
for row in range(image_row - 1, 0, -1):
    for col in range(image_col - 1, 0, -1):
        if bottom_to_top[row, col] == weak:
            if bottom_to_top[row, col + 1] == 255 or bottom_to_top[row, col - 1] == 255 or bottom_to_top[row - 1, col] == 255 or bottom_to_top[
                row + 1, col] == 255 or bottom_to_top[
                row - 1, col - 1] == 255 or bottom_to_top[row + 1, col - 1] == 255 or bottom_to_top[row - 1, col + 1] == 255 or bottom_to_top[
                row + 1, col + 1] == 255:
                bottom_to_top[row, col] = 255
            else:
                bottom_to_top[row, col] = 0
 
right_to_left = image.copy()
 
for row in range(1, image_row):
    for col in range(image_col - 1, 0, -1):
        if right_to_left[row, col] == weak:
            if right_to_left[row, col + 1] == 255 or right_to_left[row, col - 1] == 255 or right_to_left[row - 1, col] == 255 or right_to_left[
                row + 1, col] == 255 or right_to_left[
                row - 1, col - 1] == 255 or right_to_left[row + 1, col - 1] == 255 or right_to_left[row - 1, col + 1] == 255 or right_to_left[
                row + 1, col + 1] == 255:
                right_to_left[row, col] = 255
            else:
                right_to_left[row, col] = 0
 
left_to_right = image.copy()
 
for row in range(image_row - 1, 0, -1):
    for col in range(1, image_col):
        if left_to_right[row, col] == weak:
            if left_to_right[row, col + 1] == 255 or left_to_right[row, col - 1] == 255 or left_to_right[row - 1, col] == 255 or left_to_right[
                row + 1, col] == 255 or left_to_right[
                row - 1, col - 1] == 255 or left_to_right[row + 1, col - 1] == 255 or left_to_right[row - 1, col + 1] == 255 or left_to_right[
                row + 1, col + 1] == 255:
                left_to_right[row, col] = 255
            else:
                left_to_right[row, col] = 0