diff --git a/Tools/unicode/mkstringprep.py b/Tools/unicode/mkstringprep.py
index ead020c..4271883 100644
--- a/Tools/unicode/mkstringprep.py
+++ b/Tools/unicode/mkstringprep.py
@@ -1,9 +1,6 @@
-import re, sys
+import re
 from unicodedata import ucd_3_2_0 as unicodedata
 
-if sys.maxunicode == 65535:
-    raise RuntimeError("need UCS-4 Python")
-
 def gen_category(cats):
     for i in range(0, 0x110000):
         if unicodedata.category(chr(i)) in cats: