class_docstr: A skyline is set of points which is not dominated by any other point.
  
  This implementation uses a block nested loop. Identical observations are all part of the
  skyline if applicable.
  
  Parameters
  ----------
  minimize
      A list of features for which the values need to be minimized. Can be omitted as
      long as `maximize` is specified.
  maximize
      A list of features for which the values need to be maximized. Can be omitted as
      long as `minimize` is specified.
  
  Examples
  --------
  
  Here is an example taken from [this](https://maxhalford.github.io/blog/skyline-queries/) blog post.
  
  >>> import random
  >>> from river import misc
  
  >>> city_prices = {
  ...     'Bordeaux': 4045,
  ...     'Lyon': 4547,
  ...     'Toulouse': 3278
  ... }
  
  >>> def random_house():
  ...     city = random.choice(['Bordeaux', 'Lyon', 'Toulouse'])
  ...     size = round(random.gauss(200, 50))
  ...     price = round(random.uniform(0.8, 1.2) * city_prices[city] * size)
  ...     return {'city': city, 'size': size, 'price': price}
  
  >>> skyline = misc.Skyline(minimize=['price'], maximize=['size'])
  
  >>> random.seed(42)
  
  >>> for _ in range(100):
  ...     house = random_house()
  ...     skyline.update(house)
  
  >>> print(len(skyline))
  13
  
  >>> print(skyline[0])
  {'city': 'Toulouse', 'size': 280, 'price': 763202}
  
  Here is another example using the kart data from *Mario Kart: Double Dash!!*.
  
  >>> import collections
  >>> from river import misc
  
  >>> Kart = collections.namedtuple(
  ...      'Kart',
  ...      'name speed off_road acceleration weight turbo'
  ... )
  
  >>> karts = [
  ...     Kart('Red Fire', 5, 4, 4, 5, 2),
  ...     Kart('Green Fire', 7, 3, 3, 4, 2),
  ...     Kart('Heart Coach', 4, 6, 6, 5, 2),
  ...     Kart('Bloom Coach', 6, 4, 5, 3, 2),
  ...     Kart('Turbo Yoshi', 4, 5, 6, 6, 2),
  ...     Kart('Turbo Birdo', 6, 4, 4, 7, 2),
  ...     Kart('Goo-Goo Buggy', 1, 9, 9, 2, 3),
  ...     Kart('Rattle Buggy', 2, 9, 8, 2, 3),
  ...     Kart('Toad Kart', 3, 9, 7, 2, 3),
  ...     Kart('Toadette Kart', 1, 9, 9, 2, 3),
  ...     Kart('Koopa Dasher', 2, 8, 8, 3, 3),
  ...     Kart('Para-Wing', 1, 8, 9, 3, 3),
  ...     Kart('DK Jumbo', 8, 2, 2, 8, 1),
  ...     Kart('Barrel Train', 8, 7, 3, 5, 3),
  ...     Kart('Koopa King', 9, 1, 1, 9, 1),
  ...     Kart('Bullet Blaster', 8, 1, 4, 1, 3),
  ...     Kart('Wario Car', 7, 3, 3, 7, 1),
  ...     Kart('Waluigi Racer', 5, 9, 5, 6, 2),
  ...     Kart('Piranha Pipes', 8, 7, 2, 9, 1),
  ...     Kart('Boo Pipes', 2, 9, 8, 9, 1),
  ...     Kart('Parade Kart', 7, 3, 4, 7, 3)
  ... ]
  
  >>> skyline = misc.Skyline(
  ...     maximize=['speed', 'off_road', 'acceleration', 'turbo'],
  ...     minimize=['weight']
  ... )
  
  >>> for kart in karts:
  ...     skyline.update(kart._asdict())
  
  >>> best_cart_names = [kart['name'] for kart in skyline]
  >>> for name in best_cart_names:
  ...     print(f'- {name}')
  - Green Fire
  - Heart Coach
  - Bloom Coach
  - Goo-Goo Buggy
  - Rattle Buggy
  - Toad Kart
  - Toadette Kart
  - Barrel Train
  - Koopa King
  - Bullet Blaster
  - Waluigi Racer
  - Parade Kart
  
  >>> for name in sorted(set(kart.name for kart in karts) - set(best_cart_names)):
  ...     print(f'- {name}')
  - Boo Pipes
  - DK Jumbo
  - Koopa Dasher
  - Para-Wing
  - Piranha Pipes
  - Red Fire
  - Turbo Birdo
  - Turbo Yoshi
  - Wario Car
  
  References
  ----------
  [^1]: [Skyline queries in Python](https://maxhalford.github.io/blog/skyline-queries-in-python)
  [^2]: [Borzsony, S., Kossmann, D. and Stocker, K., 2001, April. The skyline operator. In Proceedings 17th international conference on data engineering (pp. 421-430). IEEE.](https://infolab.usc.edu/csci599/Fall2007/papers/e-1.pdf)
  [^3]: [Tao, Y. and Papadias, D., 2006. Maintaining sliding window skylines on data streams. IEEE Transactions on Knowledge and Data Engineering, 18(3), pp.377-391.](http://www.cs.ust.hk/~dimitris/PAPERS/TKDE06-Sky.pdf)
code: def __init__(
      self, minimize: list | None = None, maximize: list | None = None
  ):
      super().__init__()
  
      self.minimize = [] if minimize is None else minimize
      self.maximize = [] if maximize is None else maximize
  
      if len(self.minimize) + len(self.maximize) == 0:
          raise ValueError("At least one name has to be specified")
  
file_path: river/river/misc/skyline.py
imports: from __future__ import annotations
  import collections
  from river import base
label_desc: Use image node_id 1 to create a new Skyline object from inherited base classes: collections, base with example: obj = Skyline(minimize, maximize)