def activate_legislators(current_term, abbr):
    """
    Sets the 'active' flag on legislators and populates top-level
    district/chamber/party fields for currently serving legislators.
    """
    for legislator in db.legislators.find(
        {'roles': {'$elemMatch':
                   {settings.LEVEL_FIELD: abbr, 'term': current_term}}}):
        active_role = legislator['roles'][0]

        if not active_role.get('end_date') and active_role['type'] == 'member':
            legislator['active'] = True
            legislator['party'] = active_role.get('party', None)
            legislator['district'] = active_role.get('district', None)
            legislator['chamber'] = active_role.get('chamber', None)

        legislator['updated_at'] = datetime.datetime.utcnow()
        db.legislators.save(legislator, safe=True)
Sets the 'active' flag on legislators and populates top-level
    district/chamber/party fields for currently serving legislators.