text: import numpy as np
  
  KnnResults = tuple[np.ndarray, np.ndarray]
  
  class Space:
  	...
  
  class Index:
  	def __init__(self, space: Space, dim: int) -> None: ...
  	def add_items(self, data: np.ndarray) -> None: ...
  	def init_index(self, max_elements: int, M: int = 16, ef_construction: int = 200, seed: int = 100) -> None: ...
  	def knn_query(self, data: np.ndarray, K: int) -> KnnResults: ...
  	def set_ef(self, ef: int) -> None: ...
  