How to unzip a list of tuples into individual lists

Question

I have a list of tuples, where I want to unzip this list into two independent lists. I'm looking for some standardized operation in Python.

>>> l = [(1,2), (3,4), (8,9)]
>>> f_xxx (l)
[ [1, 3, 8], [2, 4, 9] ] 

I'm looking for a succinct and pythonic way to achieve this.

Basically, I'm hunting for inverse operation of zip() function.

Answer 1

Hello @kartik,

zip is its own inverse! Provided you use the special * operator.

>>> zip(*[('a', 1), ('b', 2), ('c', 3), ('d', 4)])
[('a', 'b', 'c', 'd'), (1, 2, 3, 4)]

The way this works is by calling zip with the arguments:

zip(('a', 1), ('b', 2), ('c', 3), ('d', 4))

except the arguments are passed to zip directly , so there's no need to worry about the number of arguments getting too big.

Hope this work!!

Thank You!!