how to get the last 4 letters within a string code example

Example: Complete the function to return the last X number of characters in the given string

def getLast(mystring, x):
    y=len(mystring) - x                  #finding index from where the string needs to be printed
    for i in range(y,(len(mystring))):   # printing from y index to end of string
        print(mystring[i],end="")
    
getLast('WGU College of IT', 13)