'Constructor; perform all slow lookups outside of the field methods'

def __init__(self):

    from dateutil import tz
    self.UTC = tz.tzutc()
    self.LOCAL = tz.gettz('Europe/Berlin')
    table = current.s3db.dvr_case_event_type
    query = ((table.code == 'FOOD') & (table.deleted != True))
    row = current.db(query).select(table.id, limitby=(0, 1)).first()
    self.FOOD = (row.id if row else None)
    self.SURPLUS_MEALS = s3_str(current.T('Surplus    Meals'))
