In python, you do not declare variables, so you're in danger of accidental fail due to typo in variable name.
in perl - you usually use strict; and such typos detected early at compile time.

Also, python regular expression have inconvenient syntax, compared to perl.
They have same power, but in python you must be noisy - you run regex, then you use it - in perl this is in one go, much cleaner.

Due to propaganda and some luck python it is widely believed that it is cleaner, but actualy it is vice versa.