operation=input("enter the operation to be performed ,sum,difference,product,division:").lower()
if operation=="sum" or operation=="division" or operation=="difference" or operation=="product":
num1=int(input("inserted number 1:"))
num2=int(input("inserted number 2 :"))
if operation =="sum":
sum=num1+num2
print("sum of these two numbers is:",sum)
elif operation=="product":
product=num1*num2
print("product of these two numbers is:",product)
elif operation=="difference":
difference=num1-num2
print("difference of these two numbers is:",difference)
elif operation=="division":
if num2==0:
print("Division by 0 is Invalid")
else:
division=num1/num2
print("result of dividing num1 by num2:",division)
else:
print("Please Enter a defined Operation")