const o = Object.create(null, {
  m: {value: function() {}, enumerable: true},
  "2": {value: "2", enumerable: true},
  "b": {value: "b", enumerable: true},
  0: {value: 0, enumerable: true},
  [Symbol()]: {value: "sym", enumerable: true},
  "1": {value: "1", enumerable: true},
  "a": {value: "a", enumerable: true},
});
 
console.log('--= for..in =--');
 
for (const key in o) {
	console.log(key);
}
 
console.log('\n--= Object.keys =--');
 
for (const key of Object.keys(o)) {
	console.log(key);
}
 
console.log('\n--= Object.values =--');
 
for (const value of Object.values(o)) {
	console.log(value);
}

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