Nested if and expected an indent block

[kagard@gmail.com]

Greetings:

I'm brand new to Python and decided to write a syllogism solver for a
class I'm taking. At the start of the program, I define a function that
classifies the type of each statement in the syllogism. Python tells me
that it is expecting an indented block at the s in "some". I can see
what I'm doing wrong. Here's the code:

def class_stmt(q,c):
"""
This function classifies a statement according to the rules of
categorical syllogisms and returns A, E, I, O to identify the
statement type.
"""
    if q.lower() == "all":
        if "not" in c:
            stmt_type = "E"
        else:
            stmt_type = "A"
    elif q.lower() == "some"    # s in some is highlighted
        if "not" in c:
            stmt_type = "O"
        else:
            stmt_type = "I"
    elif q.lower() == "no":
        if "not" in c:
            stmt_type = "A"
        else:
        stmt_type = "E"
    else:
        if "not" in c:
            stmt_type = "E"
        else:
            stmt_type = "A"

    return stmt_type

Any ideas? Thanks in advance.

Keith