将计数器方法转换为字典返回错误

Question

我正在尝试在python中使用Counter方法，然后转换为字典。然而，元素列表非常大(约4200个元素)。所以这个函数应该打印元素和它的频率但是它给出了一个错误:ValueError: too many values to unpack (expected 2)

from collections import Counter 
def contribution(competition):


users = Counter(['Filipe Andrew', 'M. B, Jnr, 'Retro P', 'Filipe Andrew', ...]) #up to 4200 elements

users_dict = dict(users)
for user, num_contribution in users_dict:
print(user, ' -> ', num_contribution) 

contribution('year 2015_in_Brazil')```

Answer 1

items()方法返回一个视图对象。视图对象包含字典的键值对，就像列表中的元组一样。字典中的items方法返回一个字典项，即dict_items([('Filipe Andrew'， 1)， ('M. B, Jnr, 1)， ('Retro P'， 1)])

解决方案:

from collections import Counter 
def contribution(competition):


users = Counter(['Filipe Andrew', 'M. B, Jnr, 'Retro P', 'Filipe Andrew', ...]) #up to 4200 elements

for user, num_contribution in users.items():
print(user, ' -> ', num_contribution) 

contribution('year 2015_in_Brazil')