fieldslices = [slice(*fielddef) for fielddef in [(0, 4), (4, 21), (21, 42),
    (42, 56), (56, 58)]]
fields = 'id name address city state'.split()
for rec in data:
    for field, sl in zip(fields, fieldslices):
        print(field, ':', rec[sl])
print()
Python slice how-to, I know the Python slice but how can I use built-in slice object for it?