Flatten list of list into list for dictionary

Question

I have a dictionary that looks like this:

{'data': [['748','','285','102','76024']]}

and I want to flatten the lists to look like this:

{'data': ['748','','285','102','76024']}

I have tried this from here:

[item for sublist in data.items() for item in sublist]

but it gives me:

['data', [['748', '', '285', '102', '76024', '88', '3', '89%831', '77%', '', '68%632', '19%177', '13%120']]]

`{k: v[0] for k, v in my_dict.items()}` ? – jfaccioni Aug 12 '21 at 16:20 — jfaccioni, Aug 12 '21 at 16:20

score 1 · Accepted Answer · answered Aug 12 '21 at 16:23

Based on the title, I noticed that you might have list of lists in each item in your dictionary. Using itertools.chain() you can merge multiple lists into one:

import itertools
data = {'data': [['748','','285','102','76024']]}
data1 = {'data': [['748','','285','102','76024'], ['12', '13', '14']]}

output = {k: list(itertools.chain(*v)) for k,v in data.items()}   
output1 = {k: list(itertools.chain(*v)) for k,v in data1.items()}

Output:

# Output
{'data': ['748', '', '285', '102', '76024']}

# Output1
{'data': ['748', '', '285', '102', '76024', '12', '13', '14']}

Flatten list of list into list for dictionary

1 Answers1