March, 19th 2024
The setdefault
feature is available for Python dictionaries.
Consider you have a dictionary typed as such:
mydict: dict[str, list[int]] = {}
# mydict can look like this:
# >>> {"A": [1,2,3], "B": [4,5,6]}
And you have a routine that will populate this dictionary as such:
if my_dict.get(key) is None:
my_dict[key] = [value]
else:
my_dict[key].append(value)
One way to make it all in the same line of code is by using setdefault
:
my_dict.setdefault(key, []).append(value)