Exercise for reference: 

The code produces an error. Please understand the error and try to fix it

age = input("What's your age? ")
age_last_year = age - 1
print("Last year you were %s." % age_last_year)

Answer 1: 

age = int(input("What's your age? "))
age_last_year = age - 1
print("Last year you were %s." % age_last_year)

Explanation 1:

As you can see, we applied an int  function to the input  function. That converts user input to an integer right away.

Answer 2: 

age = input("What's your age? ")
age_last_year = int(age) - 1
print("Last year you were %s." % age_last_year)

Explanation 2:

In this alternative solution, we applied the int  function in the line where the math operation occurs. This could be useful if you intend to use the user input value as a string in other parts of your script, so you don't want to convert it to an integer directly.