How to use the refextract.references.pdf.IncompleteCoordinatesError function in refextract

def _destination_position(pdf, destination):
    """
    Gives a tuple (page, column, -y, x) representing the position of the
    NamedDestination

    This representation is useful for sorting named destinations and
    assumes the text has at most 2 columns
    """
    pagewidth = pdf.getPage(
        pdf.getDestinationPageNumber(destination)
    ).cropBox.lowerRight[0]
    if not destination.left or not destination.top:
        raise IncompleteCoordinatesError(destination)
    # assuming max 2 columns
    column = (2 * destination.left) // pagewidth
    return (pdf.getDestinationPageNumber(destination),
            column, -destination.top, destination.left)