[Bug #1622533] Make docstrings raw strings because they contain control characters (\0, \1)
diff --git a/Lib/StringIO.py b/Lib/StringIO.py
index 1e5f254..232009f 100644
--- a/Lib/StringIO.py
+++ b/Lib/StringIO.py
@@ -137,7 +137,7 @@
         return r
 
     def readline(self, length=None):
-        """Read one entire line from the file.
+        r"""Read one entire line from the file.
 
         A trailing newline character is kept in the string (but may be absent
         when a file ends with an incomplete line). If the size argument is