Extract the last three String elements
Return the last 3 letters of the given string.
Sample Code:
def lastThree(str):
# Enter your logic here...
Examples:
Input: 'Codetisan'
Output: 'san'
Explanation: 'san' is the last 3 letters.
Input: '01100011'
Output: '011'
Explanation: '011' is the last 3 letters.
