'Constructor
@param site_id: the site ID (defaults to default site)
@param date: the date of the report (defaults to today)'

def __init__(self, site_id=None, date=None):

    if (site_id is None):
        site_id = current.deployment_settings.get_org_default_site()
    self.site_id = site_id
    if (date is None):
        date = current.request.utcnow.date()
    self.date = date
