bpo-38353: Cleanup includes in the internal C API (GH-16548)
Use forward declaration of types to avoid includes in the internal C
API. Add also comment to justify other includes.
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 55b2519..0526225 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -40,9 +40,10 @@
#define PY_SSIZE_T_CLEAN
#include "Python.h"
-#include "pycore_initconfig.h"
#include "pycore_fileutils.h"
+#include "pycore_initconfig.h"
#include "pycore_object.h"
+#include "pycore_pathconfig.h"
#include "pycore_pylifecycle.h"
#include "pycore_pystate.h"
#include "ucnhash.h"