Comparing the first and last character of a string in python

Question

first_and_last function returns True if the first letter of the string is the same as the last letter of the string, False if they’re different, by accessing characters using message[0] or message[-1]. While checking the condition for an empty string I get tihis error:

Error on line 2:
    if message[0] == message[1] :
IndexError: string index out of range

I dont understand why am I getting this error. Here's my code below:

 def first_and_last(message):
        if message[0] == message[-1] or len(message) == 0:
            return True
     
        else:
            return False
    
    print(first_and_last("else"))
    print(first_and_last("tree"))
    print(first_and_last("")) 

Answer 1

or stops evaluating operands on the first truthy operand. Hence, you must check the message length first in order to avoid the indexed access into the empty string:

def first_and_last(message):
    if len(message) == 0 or message[0] == message[-1]:
        return True
    return False

Or shorter:

def first_and_last(message):
    return not message or message[0] == message[-1]