Format string in python with variable formatting

Question

How can I use variables to format my variables?

cart = {\"pinapple\": 1, \"towel\": 4, \"lube\": 1}
column_width = max(len(item) for item in items)
for item, qty         


        

Answer 1

Since python 3.6 you can use f-strings resulting in more terse implementation:

>>> things = {"car": 4, "airplane": 1, "house": 2}
>>> width = max(len(thing) for thing in things)
>>> for thing, quantity in things.items():
...     print(f"{thing:{width}} : {quantity}")
... 
car      : 4
airplane : 1
house    : 2
>>> 

Answer 2

Okay, problem solved already, here's the answer for future reference: variables can be nested, so this works perfectly fine:

for item, qty in cart.items():
    print "{0:{1}} - {2}".format(item, column_width, qty)