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|context> => |context: algebra play>

supported-ops |*> => |op: foo>
foo |*> #=> algebra(""|_self>,|^>,|3>)

supported-ops |x> => |op: >
 |x> => |a>

supported-ops |y> => |op: >
 |y> => |a> + |b>

supported-ops |z> => |op: >
 |z> => |a> + |b> + |c>
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