Creating a dictionary from 2 lists with duplicate keys

Question

Though I have seen versions of my issue whereby a dictionary was created from two lists (one list with the keys, and the other with the corresponding values), I want to crea

Answer 1

As already mentioned, your desired output is not possible as dictionary keys must be unique.

Below are 2 alternatives if you do not want to lose data.

List of tuples

res = [(i, j) for i, j in zip(keys, values)]

# [(18, [7, 8, 9]),
#  (34, [4, 5, 6]),
#  (30, [1, 2, 3]),
#  (30, [10, 11, 12]),
#  (18, [13, 14, 15])]

Dictionary of lists

from collections import defaultdict

res = defaultdict(list)

for i, j in zip(keys, values):
    res[i].append(j)

# defaultdict(list,
#             {18: [[7, 8, 9], [13, 14, 15]],
#              30: [[1, 2, 3], [10, 11, 12]],
#              34: [[4, 5, 6]]})