More typo fixes for 3.6
diff --git a/Lib/trace.py b/Lib/trace.py
index 7afbe76..ae15461 100755
--- a/Lib/trace.py
+++ b/Lib/trace.py
@@ -224,7 +224,7 @@
 
         :param show_missing: Show lines that had no hits.
         :param summary: Include coverage summary per module.
-        :param coverdir: If None, the results of each module are placed in it's
+        :param coverdir: If None, the results of each module are placed in its
                          directory, otherwise it is included in the directory
                          specified.
         """