def normalize_attribute(attr):
    """
    Normalizes the name of an attribute which is spelled in slightly different
    ways in paizo HTMLs
    """
    attr = attr.strip()
    if attr.endswith(':'):
        attr = attr[:-1] # Remove trailing ':' if any
    if attr == 'Prerequisites':
        attr = 'Prerequisite' # Normalize
    if attr == 'Note':
        attr = 'Prerequisite' # Normalize a very special case (Versatile Channeler)
    if attr == 'Benefits':
        attr = 'Benefit' # Normalize
    if attr == 'Leadership Modifiers':
        attr = 'Benefit' # Normalize a very special case (Leadership)
    assert attr in ('Prerequisite', 'Benefit', 'Normal', 'Special')
    return attr.lower()