python 实现全局变量

1. 问题：

count = 0
def Fuc(count):
print count
count += 1

for i in range(0, 10):
Fuc(count)

>>>
0
0
0
0
0
0
0
0
0
02. 全局变量：

global a
a = 3

def Fuc():
global a
print a
a = a + 1
if __name__ == "__main__":
　　global a
for i in range(10):
Fuc()print 'hello'
print a

>>>
3
4
5
6
7
8
9
10
11
12
133. 借用列表来实现：

a = [3]

def Fuc():
print a[0]
a[0] = a[0] + 1
if __name__ == "__main__":
global a
for i in range(10):
Fuc()
print 'hello'
print a[0]