Flatten a list of strings and lists of strings and lists in Python -

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• how can flatten lists without splitting strings? 4 answers

similar questions have been asked before, solutions don't work use case (e.g., making flat list out of list of lists in python , flattening shallow list in python. have list of strings , lists, embedded list can contain strings , lists. want turn simple list of strings without splitting strings list of characters.

import itertools  list_of_menuitems = ['image10', ['image00', 'image01'], ['image02', ['image03', 'image04']]] chain = itertools.chain(*list_of_menuitems) 

resulting list:

['i', 'm', 'a', 'g', 'e', '1', '0', 'image00', 'image01', 'image02', ['image03', 'image04']] 

expected result:

['image10', 'image00', 'image01', 'image02', 'image03', 'image04'] 

what's best (pythonic) way this?

the oft-repeated flatten function can applied circumstance simple modification.

from collections import iterable def flatten(coll):     in coll:             if isinstance(i, iterable) , not isinstance(i, basestring):                 subc in flatten(i):                     yield subc             else:                 yield 

basestring make sure both str , unicode objects not split.

there versions count on i not having __iter__ attribute. don't know that, because think str has attribute. but, it's worth mentioning.

(please upvote linked answer.)