dictutils.ops.count_by

dictutils.ops.count_by(items, key)

Count items by key function or path.

Parameters:

• items (Iterable[Any]) – Collection to count

• key (Union[str, Callable[[Any], Any]]) – Path string or function to extract counting key

Return type:

dict[Any, int]

Returns:

Dictionary mapping keys to counts

Example

>>> import json
>>> users = [{"role": "admin"}, {"role": "user"}, {"role": "admin"}, {"role": "guest"}]
>>> result = count_by(users, "role")
>>> print(json.dumps(result, indent=4))
{
    "admin": 2,
    "user": 1,
    "guest": 1
}