def str2bool(value):
    """
    Tries to transform a string supposed to represent a boolean to a boolean.

    Parameters
    ----------
    value : str
        The string that is transformed to a boolean.

    Returns
    -------
    boolval : bool
        The boolean representation of `value`.

    Raises
    ------
    ValueError
        If the string is not 'True' or 'False' (case independent)

    Examples
    --------
    >>> np.lib._iotools.str2bool('TRUE')
    True
    >>> np.lib._iotools.str2bool('false')
    False

    """
    value = value.upper()
    if value == 'TRUE':
        return True
    elif value == 'FALSE':
        return False
    else:
        raise ValueError("Invalid boolean")