def field(self, _context, id, type,
label='', choices=[], choicesList=None, description='',
tip='', validator=None, persist=False,
canonical=''):
if label == '':
label = id
self.fields.append(
metadatafield(type)(id, label, choices=(choicesList or choices),
description=description, tip=tip,
validator=validator, persist=persist,
canonical=canonical)
)