Add sleep sort with doctest and type hints (Hacktoberfest 2025)

sorts/sleep_sort.py

@@ -0,0 +1,43 @@
+# sorts/sleep_sort.py
+from __future__ import annotations
+
+import threading
+import time
+from typing import List
+
+
+def sleep_sort(arr: List[int]) -> List[int]:
+    """
+    "Sorts" a list by sleeping for each value's duration.
+    Fun demo – **not** for production!
+
+    >>> import random; random.seed(42)
+    >>> sleep_sort([3, 1, 4, 1, 5])
+    [1, 1, 3, 4, 5]
+    >>> sleep_sort([])
+    []
+    >>> sleep_sort([42])
+    [42]
+    """
+    if not arr:
+        return []
+
+    result: List[int] = []
+
+    def sleeper(value: int) -> None:
+        time.sleep(value / 1000.0)  # scale down for fast tests
+        result.append(value)
+
+    threads = [threading.Thread(target=sleeper, args=(x,)) for x in arr]
+    for thread in threads:
+        thread.start()
+    for thread in threads:
+        thread.join()
+
+    return result
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod(verbose=True)