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|context> => |context: shopping>

supported-ops |f> => |op: > + |op: basket> + |op: clean-basket>
 |f> => 3.000|apple> + 5.000|oranges> + |milk> + |bread> + |coffee> + |steak>
basket |f> => 3.000|apple> + 5.000|oranges> + |milk> + |bread> + |coffee> + |steak>
clean-basket |f> => |apple> + |oranges> + |milk> + |bread> + |coffee> + |steak>

supported-ops |user 1> => |op: basket> + |op: clean-basket>
basket |user 1> => |milk> + |bread> + |tea> + |bananas> + |carrots> + |chocolate>
clean-basket |user 1> => |milk> + |bread> + |tea> + |bananas> + |carrots> + |chocolate>

supported-ops |user 2> => |op: basket> + |op: clean-basket>
basket |user 2> => 4.000|apple> + |milk> + |coffee> + |steak>
clean-basket |user 2> => |apple> + |milk> + |coffee> + |steak>

supported-ops |user 3> => |op: basket> + |op: clean-basket>
basket |user 3> => |chocolate> + |vegemite> + |olive oil> + |pizza> + |cheese>
clean-basket |user 3> => |chocolate> + |vegemite> + |olive oil> + |pizza> + |cheese>

supported-ops |user 4> => |op: basket> + |op: clean-basket>
basket |user 4> => |vegemite> + |cheese> + |bread> + |salami>
clean-basket |user 4> => |vegemite> + |cheese> + |bread> + |salami>
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