How to index nested lists in Python? -

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i have nested list shown below:

a = [('a', 'b', 'c'),      ('d', 'e', 'f'),      ('g', 'h', 'i')]

and trying print first element of each list using code:

a = [('a', 'b', 'c'), ('d', 'e', 'f'), ('g', 'h', 'i')] print a[:][0]

but following output:

('a', 'b', 'c')

required output:

('a', 'd', 'g')

how output in python?

a[:] creates copy of whole list, after element 0 of copy.

you need use list comprehension here:

[tup[0] tup in a]

to list, or use tuple() generator expression tuple:

tuple(tup[0] tup in a)

demo:

>>> = [('a', 'b', 'c'), ('d', 'e', 'f'), ('g', 'h', 'i')] >>> [tup[0] tup in a] ['a', 'd', 'g'] >>> tuple(tup[0] tup in a) ('a', 'd', 'g')

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