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|context> => |context: category theory is bko?>

supported-ops |a> => |op: f>
f |a> => |b>

supported-ops |b> => |op: g>
g |b> => |c>

supported-ops |c> => |op: h>
h |c> => |d>

supported-ops |*> => |op: id> + |op: H>
id |*> #=> |_self>
H |*> #=> g f |_self>
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