Convert python list into dictionary by mapping list elements to themselves

If I have a list that looks like this:

['1 184',
 '1 29',
 '1 31',
 '1 12',
 '1 51',
 '1 102',
 '1 13',
 '1 14',
 '1 15',
 '1 57',
 '1 378',
 '1 859',
 '1 185',
 '1 30',
 '1 37',
 '1 52',
 '1 142',
 '1 195',
 '1 875',
 '1 56',
 '1 66',
 '1 95',
 '1 462',
 '1 497',
 '1 858',
 '1 876',
 '1 879',
 '1 880',
 '2 12',
 '2 15',
 '2 184',
 '2 858',
 '2 51']

And I wanted to map the first element of each string to each of the next elements tied to that first number, and get it in the format of {1 : [184, 29, 31...], 2 : [12, 15, 18, ...]}.

How could I do that?

>Solution :

If lst is your list from your question then:

out = {}
for a, b in map(str.split, lst):
    out.setdefault(int(a), []).append(int(b))

print(out)

Prints:

{
    1: [
        184,
        29,
        31,
        12,
        51,
        102,
        13,
        14,
        15,
        57,
        378,
        859,
        185,
        30,
        37,
        52,
        142,
        195,
        875,
        56,
        66,
        95,
        462,
        497,
        858,
        876,
        879,
        880,
    ],
    2: [12, 15, 184, 858, 51],
}

EDIT: To explicitly check for correct values:

out = {}
for value in lst:
    value = value.split()
    if len(value) == 2:
        a, b = value
        out.setdefault(int(a), []).append(int(b))