デコレータとyieldを使ってdictを返す関数でちょっと楽する方法 ref: https://qiita.com/kurogelee/items/1c081a5a7e209e81921c

returns.py

def returns(wrap_function):
    def decorator(f):
        def decorated(*args, **kwargs):
            return wrap_function(f(*args, **kwargs))
        return decorated
    return decorator

sample.py

@returns(dict)
def times3(values):
    for v in values:
        yield v, v * 3

print(times3([1, 3, 5]))  # {1: 3, 3: 9, 5: 15}

sample_old.py

def times3_old(values):
    result = {}
    for v in values:
        result[v] = v * 3
    return result

print(times3_old([1, 3, 5]))  # {1: 3, 3: 9, 5: 15}