Python:Nested function Aren't Nested Scope

def outer(x):
    def inner(i):    #assign in outer's local
        print (i)    #i is in inner local
        if i:inner(i-1):#not in my local or global
    inner(x)


>>outer(3)
trackback......
NameError




def outer(x):
    global inner
    def inner(x): #assign in enclosing module
        print (i)
        if i: inner(i-1)#found in my global scope now
    inner(x)




>>outer(3)
3 2 1 0