2, 3])
    [1, 2, 3]

    For an ndarray-backed Series / Index the ndarray is returned.

    >>> extract_array(pd.Series([1, 2, 3]))
    array([1, 2, 3])

    To extract all the way down to the ndarray, pass ``extract_numpy=True``.

    >>> extract_array(pd.Series([1, 2, 3]), extract_numpy=True)
    array([1, 2, 3])
    Z