Allow empty name if handle is non-null in CDLL

Author: aisk

Lib/ctypes/__init__.py

@@ -443,7 +443,7 @@ def __init__(self, name, mode=DEFAULT_MODE, handle=None,
             else:
                 import nt
                 mode = nt._LOAD_LIBRARY_SEARCH_DEFAULT_DIRS
-                if '/' in name or '\\' in name:
+                if name is not None and ('/' in name or '\\' in name):
                     self._name = nt._getfullpathname(self._name)
                     mode |= nt._LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR