(;
AB[bb][bc][cb][ae][be][ce][de][dd][ec][fc][gc][gb][ga]
AW[ca][db][eb][fb][fa][dc][cc][cd][bd][ad]
C[Black plays.]
(;
B[da]
C[The only move.];
W[ab]
(;
B[aa]
C[Did you spot this cunning throw in?];
W[ba];B[aa];W[ba];B[ca]
C[Now Black has just enough liberties to give atari.  The result is a direct ko that Black takes 1st.

How did you do?]
)
    (;
    B[ba]
    C[Fails.];
    W[ac]
    C[White has  a gote seki for life.]
    )
)
    (;
    B[ba]
    C[A mistake.];
    W[ac];B[da];W[ab]
    C[White has a gote seki for life.]
    )
)

