How to use the larray.core.array.LArrayPointsIndexer function in larray

if any(k is None for k in key):
                        return missing_value
                elif isinstance(key, slice):
                    raise NotImplementedError()
                else:
                    # scalar or array key
                    key = fixkey(key, filter_value)
                    if key is None:
                        return missing_value
            else:
                if not filter_value:
                    if (non_scalar_array(key) or
                        (isinstance(key, tuple) and
                         any(non_scalar_array(k) for k in key))):
                        # scalar filter, array or tuple key
                        if isinstance(expr_value, la.core.array.LArrayPointsIndexer):
                            expr_value = expr_value.array
                        return np.full_like(expr_value, missing_value)
                    elif isinstance(key, slice):
                        raise NotImplementedError()
                    else:
                        # scalar (or tuple of scalars) key
                        return missing_value
        # print("fixed key", key)
        return expr_value[key]