import re
input = ['90-10-07457', '000480087800784', '001-713-0926', '12-710-8197', '1-345-1715', '9-23-4532', '000200007100272']
output = ['00090-00010-07457', '000480087800784', '00001-00713-00926', '00012-00710-08197', '00001-00345-01715', '00009-00023-04532', '000200007100272']
 
## I have tried this -
 
import re
new_list = []
for i in range (0, len(input)):
    new_list.append(re.sub(r'^(\d+)-(\d+)-(\d+)$', lambda x: "{}-{}-{}".format(x.group(1).zfill(5), x.group(2).zfill(5), x.group(3).zfill(5)), input[i]))
 
## problem is with second argument '0000\\1'. I know its wrong but unable to solve
print(new_list)  ## new_list is the expected output.
print(output)

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