Issue #16421: allow to load multiple modules from the same shared object.

Patch by Václav Šmilauer.
diff --git a/PCbuild/_testimportmultiple.vcxproj.filters b/PCbuild/_testimportmultiple.vcxproj.filters
new file mode 100644
index 0000000..db0d0a6
--- /dev/null
+++ b/PCbuild/_testimportmultiple.vcxproj.filters
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <Filter Include="Source Files">
+      <UniqueIdentifier>{1ec38ad9-1abf-4b80-8628-ac43ccba324b}</UniqueIdentifier>
+    </Filter>
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="..\Modules\_testimportmultiple.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+  </ItemGroup>
+</Project>