What about this:
answer = raw_input("Your answer: ")
if answer.lower() in ("2", "two"):
# Answer was good.
This method takes the answer, makes it lowercase, and then sees if it can be found in the tuple ("2", "two")
. It will return True
for input such as:
"Two"
"two"
"2"
"tWo"
etc. Anything else will have it return False
.