| 1234567891011121314151617181920 | // https://github.com/tc39/proposal-iterator-helpersvar $ = require('../internals/export');var call = require('../internals/function-call');var isPrototypeOf = require('../internals/object-is-prototype-of');var IteratorPrototype = require('../internals/iterators-core').IteratorPrototype;var createIteratorProxy = require('../internals/iterator-create-proxy');var getIteratorFlattenable = require('../internals/get-iterator-flattenable');var IteratorProxy = createIteratorProxy(function () {  return call(this.next, this.iterator);}, true);$({ target: 'Iterator', stat: true, forced: true }, {  from: function from(O) {    var iteratorRecord = getIteratorFlattenable(O);    return isPrototypeOf(IteratorPrototype, iteratorRecord.iterator)      ? iteratorRecord.iterator      : new IteratorProxy(iteratorRecord);  }});
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