bpo-40325: Deprecate set object support in random.sample() (GH-19591)
diff --git a/Doc/library/random.rst b/Doc/library/random.rst
index 9964af4..82e900d 100644
--- a/Doc/library/random.rst
+++ b/Doc/library/random.rst
@@ -230,6 +230,13 @@
If the sample size is larger than the population size, a :exc:`ValueError`
is raised.
+ .. deprecated:: 3.9
+ In the future, the *population* must be a sequence. Instances of
+ :class:`set` are no longer supported. The set must first be converted
+ to a :class:`list` or :class:`tuple`, preferably in a deterministic
+ order so that the sample is reproducible.
+
+
Real-valued distributions
-------------------------