Scoping.py源代码分析

x = 1 # global variable#全局变量# alters the local variable x, shadows the global variabledef a(): x = 25 #局部变量 print "/nlocal x in a is", x, "after entering a" #打印局部变量 x += 1 print "local x in a is", x, "before exiting a" #打印变化后的局部变量# alters the global variable xdef b(): global x #声明使用全局变量x print "/nglobal x is", x, "on entering b" 打印全局变量 x *= 10 #修改全局变量 print "global x is", x, "on exiting b" #打印修改后的全局变量print "global x is", x#再次打印全局变量x = 7print "global x is", x#运行时，首次修改全局x，并打印a()b()a()b()print "/nglobal x is", x