Optimizing Fixed Width File Parsing

To efficiently parse fixed-width files, one may consider leveraging Python's struct module. This approach leverages C for improved speed, as demonstrated in the following example:

import struct

fieldwidths = (2, -10, 24)
fmtstring = ' '.join('{}{}'.format(abs(fw), 'x' if fw 
Alternatively, string slicing can be employed. To enhance efficiency, consider defining a lambda function that compiles slices at runtime, as seen in the below optimized version:
def make_parser(fieldwidths):
    cuts = tuple(cut for cut in accumulate(abs(fw) for fw in fieldwidths))
    pads = tuple(fw