def get(self, id, pk='id', deleted=False):
        try:
            if pk == 'id':
                id = int(id)
            if deleted:
                spec = {pk: id}
            else:
                spec = {pk: id, 'data': {'$exists': 1}}
            fields = {'_id': 0}
            row = self.db.docs.find_one(spec, fields)
        except Exception as e:
            raise DatabaseException(e)
        if row:
            return Document(**row)
        raise NotFoundError('%s %s not found' % (pk, id))
def _get_path(self, prefix, override_receipt_id=None):
        """
        Returns the path to a resource with this instance's `receipt_id`.

        If `override_receipt_id` is given, the path to that resource will be
        retrieved instead. This allows us to retrieve images submitted in
        previous attempts (used for reverification, where we send a new face
        photo with the same photo ID from a previous attempt).
        """
        receipt_id = self.receipt_id if override_receipt_id is None else override_receipt_id
        return os.path.join(prefix, receipt_id)