def __init__(self, client, group=None, is_joined=True):

        self._client = client
        self._group  = group

        self.id      = group.id
        self.name    = group.name

        self.is_joined = is_joined

        try:
            self.creator = LineContact(client, group.creator)
        except:
            self.creator = None

        self.members = [LineContact(client, member) for member in group.members]

        try:
            self.invitee = [LineContact(client, member) for member in group.invitee]
        except TypeError:
            self.invitee = []
Construct a form class that has all the fields and formsets named in
dataset/ETHPy150Open carpedm20/LINE/line/models.py/LineGroup.__init__--crossover with--dataset/ETHPy150Open torchbox/wagtail/wagtail/wagtailadmin/edit_handlers.py/BaseFormEditHandler.get_form_class