Python – unpack_from requires a buffer of at least 1164 bytes

I’m using structs to parse fixed-width strings. However, I’m having some trouble working with fixed-width strings larger than 1000 bytes.

For example, when I execute the following code:

import struct
fmt =  '2s25s16s1s40s2s1s1s2s9s1s6s10s25s2s2s9s8s2s2s4x8s2x2s2s2s2s2s1x13s6s2s2s2s2s1x3s4s6s4s12x1s2s1x7s1s2s2s2s2s2s1x3s6x2s2x2s2x2s2x2s2x2s2x2s6s2x1s4x4s2s2s2s2s2s2s2s8x3s3s3s3s3s3s3s3s3s2s2s2s2s2s2s8s2x2s2s2s2s2 s150s50s4x1s2s8s15x30s30s10s15s15s10s10s10s10s12s3s3s3s3s1s3s3s1x15s2s3s8s2s2s2s2s2s16s2s3s2x2s3s2x1s1s2s2s3s3s2s2s3s3s2s2s3s3s2s2s3s3s2s2s3s3s2s2s3s3s2s2s3s3s2s2s3s3s2s2s3s3s2s2s3s3s2s2s3s3s10x2s2s3s3s2s2s3s 3s2s2s3s3s2s2s3s3s2s2s3s3s2s2s3s3s42s6s21s3s3s3s3s3s3s3s3s3s3s3s3s7s'
parse = struct. Struct(fmt).unpack_from

line =  '1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOP QRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGH IJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890 ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ12 34567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRST UVWXYZ123456'
parse(line.encode())

I get the following error:

Traceback (most recent call last):
  File "so.py", line 6, in <module>
    parse(line.encode())
struct.error: unpack_from requires a buffer of at least 1164 bytes

I’ve been looking for a way to set the buffer to 1164 bytes without success.