Favorite Python One-liners
May 21, 2015
So, these are not really one-liners as much as they are useful snippets of code I seem to always use or always look for. Feel free to add your own in the comments.
Decode base64 File
import base64, sys; base64.decode(open(sys.argv, "rb"), open(sys.argv, "wb"))
Min and Max
print min([1, 5, 2, -1, 0]) print max([1, 5, 2, -1, 0])
Cache Function Results for Faster Performance (Decorators)
You've got some extra work on your hands if you want to use this before Python 3.2.3.
import functools @functools.lru_cache(maxsize=None) def fib(n): return 1 if n < 2 else fib(n-1) + fib(n-2) print fib(5)
x = 1 y = 2 x, y = y, x print x print y
Interate Over 2 Lists in 1 Loop
list1 = ["apples", "oranges"] list2 = ["bag", "bucket"] for a, b in zip(list1, list2): print a + " are in a " + b
Hackery with FizzBuzz
for x in range(1,101): print "Fizz" [x%3*4:] + "Buzz" [x%5*4:] or x
Write to File
with open('foo.txt', 'w') as f: f.write('hello world')
Read File Lines Into Array Stripped
lines = [line.strip() for line in open('foo.txt')]
Evaluate a String as as Python
expression = "[1, 2, 3, 4, 5]" list = eval(expression) print list
Set a Breakpoint in Your Script
Just call pdb.set_trace() anywhere in your script to set a breakpoint.
import pdb pdb.set_trace()
Profile Your Script
import profile profile.run("func()")
Start A Web ServerStart a web service on port 8000 that uses the current directory as its document root.
python -m SimpleHTTPServer