bpo-32436: Implement PEP 567 (#5027)

diff --git a/PCbuild/pythoncore.vcxproj b/PCbuild/pythoncore.vcxproj
index bf2ce66..fbcd051 100644
--- a/PCbuild/pythoncore.vcxproj
+++ b/PCbuild/pythoncore.vcxproj
@@ -94,6 +94,7 @@
     <ClInclude Include="..\Include\codecs.h" />
     <ClInclude Include="..\Include\compile.h" />
     <ClInclude Include="..\Include\complexobject.h" />
+    <ClInclude Include="..\Include\context.h" />
     <ClInclude Include="..\Include\datetime.h" />
     <ClInclude Include="..\Include\descrobject.h" />
     <ClInclude Include="..\Include\dictobject.h" />
@@ -112,7 +113,9 @@
     <ClInclude Include="..\Include\import.h" />
     <ClInclude Include="..\Include\internal\ceval.h" />
     <ClInclude Include="..\Include\internal\condvar.h" />
+    <ClInclude Include="..\Include\internal\context.h" />
     <ClInclude Include="..\Include\internal\gil.h" />
+    <ClInclude Include="..\Include\internal\hamt.h" />
     <ClInclude Include="..\Include\internal\mem.h" />
     <ClInclude Include="..\Include\internal\pystate.h" />
     <ClInclude Include="..\Include\internal\warnings.h" />
@@ -232,6 +235,7 @@
     <ClCompile Include="..\Modules\_blake2\blake2s_impl.c" />
     <ClCompile Include="..\Modules\_codecsmodule.c" />
     <ClCompile Include="..\Modules\_collectionsmodule.c" />
+    <ClCompile Include="..\Modules\_contextvarsmodule.c" />
     <ClCompile Include="..\Modules\_csv.c" />
     <ClCompile Include="..\Modules\_functoolsmodule.c" />
     <ClCompile Include="..\Modules\_heapqmodule.c" />
@@ -359,6 +363,7 @@
     <ClCompile Include="..\Python\ceval.c" />
     <ClCompile Include="..\Python\codecs.c" />
     <ClCompile Include="..\Python\compile.c" />
+    <ClCompile Include="..\Python\context.c" />
     <ClCompile Include="..\Python\dynamic_annotations.c" />
     <ClCompile Include="..\Python\dynload_win.c" />
     <ClCompile Include="..\Python\errors.c" />
@@ -373,6 +378,7 @@
     <ClCompile Include="..\Python\getplatform.c" />
     <ClCompile Include="..\Python\getversion.c" />
     <ClCompile Include="..\Python\graminit.c" />
+    <ClCompile Include="..\Python\hamt.c" />
     <ClCompile Include="..\Python\import.c" />
     <ClCompile Include="..\Python\importdl.c" />
     <ClCompile Include="..\Python\marshal.c" />