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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def as_indexable(array):
 """ This function always returns a ExplicitlyIndexed subclass, so that the vectorized indexing is always possible with the returned object. """

    if isinstance(array, ExplicitlyIndexed):
        return array
    if isinstance(array, np.ndarray):
        return NumpyIndexingAdapter(array)
    if isinstance(array, pd.Index):
        return PandasIndexAdapter(array)
    if isinstance(array, dask_array_type):
        return DaskIndexingAdapter(array)
    raise TypeError('Invalid array type: {}'.format(type(array)))