Count the number of final elements in a dict. This function works for nested dict. Each final value is stored in a list.

count_leaves_dict.py

def count_leaves_dict(element:dict) -> int:
    if isinstance(element, list): return len(element)
    if not isinstance(element, dict): raise Exception("Wrong data type")
    nb_leaves = 0
    for _, value in element.items():
        nb_leaves += count_leaves_dict(value)
    return nb_leaves

Example of a good dict :

d = {
    'a' : [1,2,3,4],
    'b' : {
        'ba':[5,6,7], 
        'bb':[8,9]
        }
}

Result = 9