If you wonder why crc32(crack(x)) not equal to x

[basinilya]

crack() returns List of int, but these Integers should not be hashed as 32 bits directly. You need to format them as decimal strings, then treat each digit as an ASCII character and update CRC32 with it.

crack() will return an empty list if it can't find a relatively short sequence of decimal characters even if the given hash can be computed with letters or non-printable bytes.