diff --git a/pep-0343.txt b/pep-0343.txt
index 57b58d026..2e9884712 100644
--- a/pep-0343.txt
+++ b/pep-0343.txt
@@ -414,7 +414,9 @@ Examples
                     num *= x * x
                     sign *= -1
                     s += num / fact * sign
-                return +s
+            # The "+s" rounds back to the original precision,
+            # so this must be outside the do-statement:
+            return +s
 
        An alternative version of the generator saves the entire
        context instead of just the precision attribute.  This is more