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            {
              "args": [
                {
                  "coins-inserted": [],
                  "coins-returned": ["quarter", "quarter", "nickel"],
                  "dispensed": { "name": "taco", "qty": 10, "price": 0.85 },
                  "inventory": { "a1": { "name": "taco", "qty": 9, "price": 0.85 } },
                  "err-msg": null
                }