from dio import b a=10 print(b) a=10 def b(): global a # input global a variable in function for modification a=2 print(a) print(a) b() print(a) print("=================================") #a=10 def b(): def c(): a=10 print(a) global a # input global a variable in function for modification a=2 print(a) c() b() print(a) print("+++++++++++++++++++++++++++++++") def b(): def c(): nonlocal b # b refer outer function variable b, but not global line 35 b b=10 print(b) global a # input global a variable in function for modification b=1 a=2 print(a) c() b() print(a) print("+++++++++++++++++++++++++++++++") def b(): def c(): def d(): nonlocal a # refer a in line 53 a, reference scope unable exceed the functions scope a =100 print(a) d() # global a # input global a variable in function for modification b=1 a=2 print(a) c() b() print(a)