def parse_parameter_name(key):
    m = reverseContinuation.match(reverse(key))
    key = reverse(m.group('key'))
    part = reverse(m.group('part')) if m.group('part') else None
    encoded = m.group('encoded')
    return (key, part, encoded)
New style parameter names can be splitted into parts,
dataset/ETHPy150Open mailgun/flanker/flanker/mime/message/headers/parametrized.py/parse_parameter_name