Minimum size

[perfringo]

You are on right track (lines # 6 and 7) but slight adjustments needed.

You need:

- find minimum length from list elements
- find elements which length is equal to minimum length

>>> lst = [['1', '6', '66', '9', '33'], 
...        ['1', '6', '9', '33'], 
...        ['1', '66', '6', '9', '33'], 
...        ['1', '66', '9', '33'], 
...        ['1', '4', '9', '33']] 
>>> shortest = min(len(row) for row in lst) 
>>> shortest
4
>>> [row for row in lst if len(row) == shortest] 
[['1', '6', '9', '33'], ['1', '66', '9', '33'], ['1', '4', '9', '33']]