cannot figure out

[nilamo]

I can't reproduce the issue, so please show us the output you're getting (your code looks fine to me, though I'd suggest using .lower() instead of handling both upper and lower case characters... or using "in" like if ti in "tTiI", or both: if ti.lower() in "it"):

>>> ti = input("? ")
? spam
>>> if ti=='t' or ti=='T' or ti=='i' or ti=='I':
...  print("Yep")
... else:
...  print("Nope")
...
Nope