diff --git a/py/lexer.c b/py/lexer.c
index be0b188..26fec12 100644
--- a/py/lexer.c
+++ b/py/lexer.c
@@ -516,7 +516,7 @@
         }
 
         // cut off the end quotes from the token text
-        vstr_cut_tail(&lex->vstr, n_closing);
+        vstr_cut_tail_bytes(&lex->vstr, n_closing);
 
     } else if (is_head_of_identifier(lex)) {
         tok->kind = MP_TOKEN_NAME;