【说站】python自由变量是什么

def make_averager():
count = 0
total = 0
def averager(new_value):
count += 1
total += new_value
return total / count
return averager
 
 
>>> avg = make_averager()
>>> avg(10)
Traceback (most recent call last):
...
UnboundLocalError: local variable 'count' referenced before assignment

def make_averager():
    count = 0
    total = 0
    def averager(new_value):
        nonlocal count, total   # 声明count、total为自由变量
        count += 1
        total += new_value
        return total / count
    return averager