bpo-43816: Add extern "C" to Include/cpython/pyctype.h (GH-25365) (GH-25387)

Signed-off-by: Andrew V. Jones <[email protected]>
(cherry picked from commit 54db51c)

Co-authored-by: Andrew V. Jones <[email protected]>

Co-authored-by: Andrew V. Jones <[email protected]>

Author: miss-islington

Include/pyctype.h

@@ -1,6 +1,9 @@
 #ifndef Py_LIMITED_API
 #ifndef PYCTYPE_H
 #define PYCTYPE_H
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 #define PY_CTF_LOWER  0x01
 #define PY_CTF_UPPER  0x02
@@ -29,5 +32,8 @@ PyAPI_DATA(const unsigned char) _Py_ctype_toupper[256];
 #define Py_TOLOWER(c) (_Py_ctype_tolower[Py_CHARMASK(c)])
 #define Py_TOUPPER(c) (_Py_ctype_toupper[Py_CHARMASK(c)])
 
+#ifdef __cplusplus
+}
+#endif
 #endif /* !PYCTYPE_H */
 #endif /* !Py_LIMITED_API */