Python program to Check for Non-Existence of Number

x = 210 y = 130 z = 240 value = input("Insert variable x,y,z only: ") try: exec("print("+value+")") except NameError: print("Incorrect variable name!")

 

 

Output:

 

Insert variable x,y,z only: y
130

Insert variable x,y,z only: a
Incorrect variable name!