print("      String interpolation ")
x=10
y=20
# print("x == ", x ," y == ",  y)
# print(" x +y == ", x+y)
# print("x == {}  y == {} x+y == {}".format(50 , 49 ,50+49))



print("x == {first}  y == {second} x+y == {third}".format(third=x+y ,first=x , second=x  ) )


