Fix typo of hexidecimal
diff --git a/Modules/future_builtins.c b/Modules/future_builtins.c
index d5c136a..686925d 100644
--- a/Modules/future_builtins.c
+++ b/Modules/future_builtins.c
@@ -14,7 +14,7 @@
 \n\
 Functions:\n\
 \n\
-hex(arg) -- Returns the hexidecimal representation of an integer\n\
+hex(arg) -- Returns the hexadecimal representation of an integer\n\
 oct(arg) -- Returns the octal representation of an integer\n\
 \n\
 The typical usage of this module is to replace existing builtins in a\n\