Remove extraneous #define as per effbot's instructions in:

nnorwitz · nnorwitz · commit 5909402cde79 · 2002-03-18T18:46:14.000Z
[ 530285 ] redefining SRE_CODE in Modules/sre.h
diff --git a/Modules/sre.h b/Modules/sre.h
@@ -21,8 +21,6 @@
 #define SRE_CODE unsigned short
 #endif
 
-#define SRE_CODE unsigned short
-
 typedef struct {
     PyObject_VAR_HEAD
     int groups; /* must be first! */
