python nested list to list code example

Example 1: flatten a list of list python

# idiomatic python

# using itertools
import itertools

list_of_list = [[1, 2, 3], [4, 5], [6]]
chain = itertools.chain(*images)

flattened_list = list(chain)
# [1, 2, 3, 4, 5, 6]

Example 2: python nested list

# example of a nested list
my_list = [[1, 2], ["one", "two"]]

# accessing a nested list
my_list[1][0] # outputs "one"

Example 3: how to make one list from nested list

>>> from collections import Iterable
def flatten(lis):
     for item in lis:
         if isinstance(item, Iterable) and not isinstance(item, str):
             for x in flatten(item):
                 yield x
         else:        
             yield item

>>> lis = [1,[2,2,2],4]
>>> list(flatten(lis))
[1, 2, 2, 2, 4]
>>> list(flatten([[1, 2, 3], [4, 5, 6], [7, 8, 9]]))
[1, 2, 3, 4, 5, 6, 7, 8, 9]

Example 4: flatten lists python

flat_list = []
for sublist in l:
    for item in sublist:
        flat_list.append(item)