Fix raw byte strings
diff --git a/src/stable.rs b/src/stable.rs
index 339797e..edf8018 100644
--- a/src/stable.rs
+++ b/src/stable.rs
@@ -268,7 +268,7 @@
     }
 
     pub fn raw_byte_string(s: &str, pounds: usize) -> Literal {
-        let mut ret = format!("rb");
+        let mut ret = format!("br");
         ret.extend((0..pounds).map(|_| "#"));
         ret.push('"');
         ret.push_str(s);