patch 8.0.0251: not easy to select Python 2 or 3
Problem: It is not so easy to write a script that works with both Python 2
and Python 3, even when the Python code works with both.
Solution: Add 'pyxversion', :pyx, etc. (Marc Weber, Ken Takata)
diff --git a/src/option.h b/src/option.h
index 0ad2fef..62e66cd 100644
--- a/src/option.h
+++ b/src/option.h
@@ -694,6 +694,9 @@
#if defined(DYNAMIC_PYTHON)
EXTERN char_u *p_pydll; /* 'pythondll' */
#endif
+#if defined(FEAT_PYTHON) || defined(FEAT_PYTHON3)
+EXTERN long p_pyx; /* 'pyxversion' */
+#endif
#ifdef FEAT_RELTIME
EXTERN long p_rdt; /* 'redrawtime' */
#endif