Adding elements in a list

This is the code with no AI.

def addEveryOtherElement(intArr):
    if intArr/2 ==0 then 
    result = intArr++
    return result

I created this code with AI. "Recursion" AI code review's suggestion as follows.

def addEveryOtherElement(intArr):
    result = 0
    for i, num in enumerate(intArr):
        if i % 2 != 0:
            result += num
    return result

My question;
Is the comma in for i, necessary? What role does it play?

AI's answer.
When using enumerate in a for loop, the enumerate function returns two values for each iteration: the element and its index. Therefore, the iterator of the for loop must specify two variables, which are separated by a comma ,.

Without comma, I got this SyntaxError so it is like using enumerate(intArr): and def addEveryOtherElement(intArr):, I have to use comma to make it aware that there are two declarative statements.

  File "script.py", line 3
    for i num in enumerate(intArr):
          ^
SyntaxError: invalid syntax