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|context> => |context: simple entanglement example>

supported-ops |particles> => |op: entanglement-1> + |op: entanglement-2> + |op: the-list-of-possible-entanglements> + |op: measure>
entanglement-1 |particles> => |particle 1: spin up> + |particle 2: spin down>
entanglement-2 |particles> => |particle 1: spin down> + |particle 2: spin up>
the-list-of-possible-entanglements |particles> => |op: entanglement-1> + |op: entanglement-2>
measure |particles> #=> apply(weighted-pick-elt the-list-of-possible-entanglements|_self>,|_self>)
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