def a(x,y): # @1.5 x=1 y=2 print(x+y) a(1,2) a(2,3) # @1.5 x=2 y=3 def b(x,y=1): # @5 x=? , y=1 print(x+y) b(1) # @5.5 x=1 b(2,3) # @5.5 x=2 y=3