bpo-32995 - Added context variable in glossary (GH-9741)

(cherry picked from commit c0a1a07)

Co-authored-by: Vinodhini Balusamy <[email protected]>

Author: miss-islington

Doc/glossary.rst

@@ -221,6 +221,15 @@ Glossary
       statement by defining :meth:`__enter__` and :meth:`__exit__` methods.
       See :pep:`343`.
 
+    context variable
+      A variable which can have different values depending on its context.
+      This is similar to Thread-Local Storage in which each execution
+      thread may have a different value for a variable. However, with context
+      variables, there may be several contexts in one execution thread and the
+      main usage for context variables is to keep track of variables in
+      concurrent asynchronous tasks.
+      See :mod:`contextvars`.
+
    contiguous
       .. index:: C-contiguous, Fortran contiguous
 

Misc/NEWS.d/next/Documentation/2018-10-07-03-04-57.bpo-32995.TXN9ur.rst

@@ -0,0 +1 @@
+Added the context variable in glossary.