for i in range(3,0,-1): # executes the loop 3 times. Giving 3 chances to the user. num = input("enter a number:") if num.isnumeric(): # checks if entered input is an ...

While we have the Python built-in function sum() which sums the elements of a sequence (provided the elements of the sequence are all of numeric type), it’s instructive to see how we can do this in a ...