How to convert a Python text file containing lists of lists into a list of lists?

Question

This seems pretty straightforward, but I can't find any alternative solutions online. I have a text file like so:

[[[0, 0, 'no'], [3, 0, 1]], [[4, 4, 'coming']]]
[[[0, 0, 'yes'], [2, 0, 2], [2, 2, '15-19']], [[9, 4, 'not coming']]]

How do I go about parsing this file in such a way where it'd follow the same logic:

# Read in file
# Work with the first line, or list, of lists 
    # Do this by putting it into a temporary list of lists variable

Is what I'm asking possible? I'm just wanting to save myself time working with a monstrous text file that'd be way easier this way.

Did you creaate the text file or is it third-party? – Neil Oct 26 '20 at 20:58 — Neil, Oct 26 '20 at 20:58
`ast.literal_eval` is safer to parse a list. – ggorlen Oct 26 '20 at 20:58 — ggorlen, Oct 26 '20 at 20:58

score 1 · Answer 1 · answered Oct 26 '20 at 21:00

You can use ast.literal_eval to parser the file:

from pprint import pprint
from ast import literal_eval

data = []
with open('<your file.txt>', 'r') as f_in:
    for line in f_in:
        data.extend(literal_eval('[' + line + ']'))

pprint(data)

Prints:

[[[[0, 0, 'no'], [3, 0, 1]], [[4, 4, 'coming']]],
 [[[0, 0, 'yes'], [2, 0, 2], [2, 2, '15-19']], [[9, 4, 'not coming']]]]

How to convert a Python text file containing lists of lists into a list of lists?

1 Answers1