The input parameter in the isWeakKey function is of type unknown,
which means it can be any type. The function checks if the input is an object (excluding null)
or a function, and returns a boolean indicating whether the input is a weak
The function isWeakKey returns a boolean value indicating whether the input is an object
or a function.
The function
isWeakKeychecks if the input is an object or a function in TypeScript.