more fix

Author: oraluben

include/pybind11/pytypes.h

@@ -321,7 +321,7 @@ PYBIND11_NAMESPACE_END(detail)
 
 #if defined(_MSC_VER)
 #  pragma warning(push)
-#  pragma warning(disable: 4275) // warning C4275: An exported class was derived from a class that wasn't exported. Can be ignored when derived from a STL class.
+#  pragma warning(disable: 4275 4251) // warning C4275: An exported class was derived from a class that wasn't exported. Can be ignored when derived from a STL class.
 #endif
 /// Fetch and hold an error which was already set in Python.  An instance of this is typically
 /// thrown to propagate python-side errors back through C++ which can either be caught manually or