Hacking __builtin__ for fun, no profit
Python's __builtin__ module contains all of the language's built-in functions, which should be reasonably obvious from the name. Python is really, really insistent that its built-ins are perfectly sufficient and that you shouldn't go around messing with them. This is a large part of the reason that I almost threw up the first time I had to go monkeypatching in Ruby... it just doesn't feel right. But for the sake of argument, let's do some screwing around with the built-in functions.
import builtin
def hex(x): '''Return the basic hex function, but with extra YOLO attached.''' f = builtin.hex(x) if f[0] == '-': return f[0] + 'yol' + f[1:] else: return 'yol' + f
The hex function is designed to return the hexadecimal representation of an integer, prefixed with 0x. I felt like this representation could be much improved with a bit of extra YOLO, and patched the function accordingly. Now I can call hex(255) and receive back "yol0xff", a marked improvement over the prior implementation.
import builtin
def len(s): '''Return the basic len function, but subtract one so we show what the last position number is.''' l = builtin.len(s) return l-1
I'm lazy, and don't always like to calculate the length of a list or string then subtract one to access the last element of a list. Why not ask len() to do that work for me? Now I can call len('hello') and receive a value of 4, allowing me to easily determine the number of the last character any time and every time.
Okay, okay... I can think of no reason why any programmer would want to go messing around with the __builtin__ library. It would be horribly un-Pythonic to start wrapping the core Python functions like this. But it's good to know that we can.