I am also getting same valueerror for below line:
increment_string
str4=int(str(newL))
ValueError: invalid literal for int() with base 10:

I am experiencing the same issue... Error part work locally but not during the tests.

Just tested, doesn't seem to have any issues anymore.

I don't get it! I pass all the tests and attempts but at the end it gives the next traceback:

Traceback:
in
in increment_string
ValueError: invalid literal for int() with base 10: '5ebuk=13/R9103471J4,#t~QUJ421518352l) 6167+RqW@s54383636231108'

Also tried using regular expressions, and they run OK in my pc, but here not, don't get why, anybody has any idea?