dazzlefruit

  JSONObject = None | str | int | bool | list["JSONObject"] | dict[str, "JSONObject"]
  # this type checks
  a: JSONObject = {"a": [1, 2, "7", True, {"false": None}]}
  # this doesn't type check
  b: JSONObject = {"a": [1, 2, "7", True, {"false": object()}]}

  from typing import TypeVar
  
  T, U, V, W = TypeVar('T'), TypeVar('U'), TypeVar('V'), TypeVar('W')
  
  def concatenate(a: tuple[T, U], b: tuple[V, W]) -> tuple[T, U, V, W]:
      return a + b

  from typing import Any, Callable
  
  Transformer = Callable[[dict[str, Any]], dict[Callable, Any]]