class GuestForm(Form):
email = TextField()
vip = BooleanField()

class VenueForm(Form):
    name = TextField()
    bio  = TextField()
    guests = FieldList(FormField(GuestForm))

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 class TelephoneForm(Form):
    country_code = IntegerField('Country Code', [validators.required()])
    area_code    = IntegerField('Area Code/Exchange', [validators.required()])
    number       = TextField('Number')

class ContactForm(Form):
    first_name   = TextField()
    last_name    = TextField()
    mobile_phone = FormField(TelephoneForm)
    office_phone = FormField(TelephoneForm)
    phones       = FieldList(FormField(TelephoneForm))