diff --git a/Lib/base64.py b/Lib/base64.py
index c196cd8a841..41a5e1470c1 100755
--- a/Lib/base64.py
+++ b/Lib/base64.py
@@ -308,7 +308,7 @@ def decode(input, output):
 
 
 def encodestring(s):
-    """Encode a string."""
+    """Encode a string into multiple lines of base-64 data."""
     pieces = []
     for i in range(0, len(s), MAXBINSIZE):
         chunk = s[i : i + MAXBINSIZE]