in operator checks if a property is in an object. It returns
true if the property is found,
hasOwnProperty() method also checks if a property is in an object. Unlike the
in operator, it doesn't check the prototype chain.
Object.keys() method returns an array of an object's own property names. You can use the
includes() method to check if a key exists.
Object.getOwnPropertyNames() method returns an array of all properties found directly upon a given object. You can also use
includes() to check for a key.
Map.has() method checks if an element with the specified key exists in a Map object.
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