add a replacement API for PyCObject, PyCapsule #5630

All stdlib modules with C-APIs now use this.

Patch by Larry Hastings
diff --git a/Include/py_curses.h b/Include/py_curses.h
index b4ad8f7..ae7b12b 100644
--- a/Include/py_curses.h
+++ b/Include/py_curses.h
@@ -75,6 +75,9 @@
 
 #define PyCursesWindow_Check(v)	 (Py_TYPE(v) == &PyCursesWindow_Type)
 
+#define PyCurses_CAPSULE_NAME "_curses._C_API"
+
+
 #ifdef CURSES_MODULE
 /* This section is used when compiling _cursesmodule.c */
 
@@ -89,16 +92,8 @@
 #define PyCursesInitialisedColor {if (! ((int (*)(void))PyCurses_API[3]) () ) return NULL;}
 
 #define import_curses() \
-{ \
-  PyObject *module = PyImport_ImportModuleNoBlock("_curses"); \
-  if (module != NULL) { \
-    PyObject *module_dict = PyModule_GetDict(module); \
-    PyObject *c_api_object = PyDict_GetItemString(module_dict, "_C_API"); \
-    if (PyCObject_Check(c_api_object)) { \
-      PyCurses_API = (void **)PyCObject_AsVoidPtr(c_api_object); \
-    } \
-  } \
-}
+    PyCurses_API = (void **)PyCapsule_Import(PyCurses_CAPSULE_NAME, 1);
+
 #endif
 
 /* general error messages */