NUM_ROWS = 4

NUM_COLS = 3

def split_ocr(ocr):

return [[ocr[i][NUM_COLS * j:NUM_COLS * (j + 1)] for i in range(NUM_ROWS)]

for j in range(len(ocr[0]) // NUM_COLS)]

ALL = [' _ _ _ _ _ _ _ _ ',

' | _| _||_||_ |_ ||_||_|| |',

' ||_ _| | _||_| ||_| _||_|',

' ']

OCR_LIST = split_ocr(ALL)

OCR_LIST = [OCR_LIST[-1]] + OCR_LIST[:9]

def convert(input_grid):

split_indices = (list(range(0, len(input_grid), NUM_ROWS)) +

[len(input_grid)])

lines = [input_grid[start:end]

for start, end in zip(split_indices[:-1], split_indices[1:])]

return ",".join(convert_one_line(line) for line in lines)

def convert_one_line(input_grid):

if (len(input_grid) != NUM_ROWS or len(input_grid[0]) % NUM_COLS or

any(len(r) != len(input_grid[0]) for r in input_grid)):

raise ValueError('Wrong grid size.')

numbers = split_ocr(input_grid)

digits = ''

for n in numbers:

try:

digits += str(OCR_LIST.index(n))

except ValueError:

digits += '?'

return digits