
{{alias}}( obj, [options,] transform )
    Inverts an object, such that keys become values and values become keys,
    according to a transform function.

    The transform function is provided three arguments:

    - `key`: object key
    - `value`: object value corresponding to `key`
    - `obj`: the input object

    The value returned by a transform function should be a value which can be
    serialized as an object key. Hence, beware when providing objects having
    values which are themselves objects. The function relies on native object
    serialization (`#toString`) when converting transform function return values
    to keys.

    Insertion order is not guaranteed, as object key enumeration is not
    specified according to the ECMAScript specification. In practice, however,
    most engines use insertion order to sort an object's keys, thus allowing for
    deterministic inversion.

    Parameters
    ----------
    obj: ObjectLike
        Input object.

    options: Object (optional)
        Options.

    options.duplicates: boolean (optional)
        Boolean indicating whether to store keys mapped to duplicate values in
        arrays. Default: `true`.

    transform: Function
        Transform function.

    Returns
    -------
    out: Object
        Inverted object.

    Examples
    --------
    // Basic usage:
    > function transform( key, value ) { return key + value; };
    > var obj = { 'a': 'beep', 'b': 'boop' };
    > var out = {{alias}}( obj, transform )
    { 'abeep': 'a', 'bboop': 'b' }

    // Duplicate values:
    > function transform( key, value ) { return value; };
    > obj = { 'a': 'beep', 'b': 'beep' };
    > out = {{alias}}( obj, transform )
    { 'beep': [ 'a', 'b' ] }

    // Override duplicate values:
    > obj = {};
    > obj.a = 'beep';
    > obj.b = 'boop';
    > obj.c = 'beep';
    > out = {{alias}}( obj, { 'duplicates': false }, transform )
    { 'beep': 'c', 'boop': 'b' }

    See Also
    --------

