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A A A A A A A A A A A A A A A A A A A A
A A A A A A A A A A A A A A A A A A A A
A A A A A A A A A A A A A A A A A A A A
A A A A A A A A A A A A A A A A A A A A
A A A A A A A A A A A A A A A A A A A A
A A A A A A A A A A A A A A A A A A A A
A A A A A A A A A A A A A A A A A A A A
A A A A A A A A A A A A A A A A A A A A
A A A A A A A A D D D A A A A A A A A A
A A A A A A A A D D D A A A A A A A A A
B B B B B B B B D D D B B B B B B B B B
B B B B B B B B B B B B B B B B B B B B
B B B B B B B B B B B B B B B B B B B B
B B B B B B B B B B B B B B B B B B B B
B B B B B B B B B B B B B B B B B B B B
B B B B B B B B B B B B B B B B B B B B
B B B B B B B B B B B B B B B B B B B B
B B B B B B B B B B B B B B B B B B B B
B B B B B B B B B B B B B B B B B B B B
B B B B B B B B B B B B B B B B B B B B