Make a dictionary with duplicate keys in Python

Question

I have the following list which contains duplicate car registration numbers with different values. I want to convert it into a dictionary which accepts this multiple keys of

Answer 1

Python dictionaries don't support duplicate keys. One way around is to store lists or sets inside the dictionary.

One easy way to achieve this is by using defaultdict:

from collections import defaultdict

data_dict = defaultdict(list)

All you have to do is replace

data_dict[regNumber] = details

with

data_dict[regNumber].append(details)

and you'll get a dictionary of lists.