# Pyhton call back function ```python= # Recall function def f(x): return 2*x+3 def g(x): return x answer = f(g(5)) print(answer) print("===============================") def normalFunction(x): return 2*x+3 def callBackFunction(x): return x answer= normalFunction(callBackFunction(10)) print(answer) print("================================") def f(x): return recallFunction(x) def recallFunction(x): return x answer = f(recallFunction(10)) print(answer) print("==================================") def f1(f2): f2() # call recall fucnction def f2(): print(100) f1(f2) print("================================") def f1(f2): f2(100) def f2(num): print(num) f1(f2) print("==================================") def add(a,b,showfunction): showfunction(a+b) def display(result): print("result is ", result) add(10,5,display) ```