[Python] Python does not throw IndexError when evaluating if condition with 'and' operator...

I am currently helping a friend with getting into python and I came across this snippet of code, where I was unable to understand what was happening.

def lbd_red(s):
try:
for i in range(len(s)):
if s.isalpha() and s[i+1].isdigit():
if s.isdigit() and s[i+1].isdigit():
print("smth")

return True
except IndexError:
return False


I would expect this function to always return False, as the if statement essentially does nothing for the control flow, but should always throw an IndexError when evaluating s[i+1]. Yet somehow this is not what is happening. Here are a few examples of function returns:

>> lbd_red("hu3")
True
>> lbd_red("hu3e")
False
>> lbd_red("hue3")
True
>> lbd_red("hue34")
True
>> lbd_red("hue34e")
False
>> lbd_red("hue33")
True
>> lbd_red("hue3e")
False


I have also tried debugging this code and when I watch s[i+1], I can see the IndexError ocurring, but it just does not seem to be thrown in the actual code.

I am currently using Python 3.10.0, but I have also tried it on Python 3.12.

PS: Yes, I know that the print statement will never be reached, but this is just some random code, its usefulness is not relevant to the question.

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