Regenerate docs. (#696)

diff --git a/docs/epy/module-tree.html b/docs/epy/module-tree.html
index 5f81214..9ee42f0 100644
--- a/docs/epy/module-tree.html
+++ b/docs/epy/module-tree.html
@@ -58,6 +58,7 @@
     <li> <strong class="uidlink"><a href="googleapiclient-module.html">googleapiclient</a></strong>
     <ul>
     <li class="private"> <strong class="uidlink"><a href="googleapiclient._auth-module.html">googleapiclient._auth</a></strong>: <em class="summary">Helpers for authentication using oauth2client or google-auth.</em>    </li>
+    <li class="private"> <strong class="uidlink"><a href="googleapiclient._helpers-module.html">googleapiclient._helpers</a></strong>: <em class="summary">Helper functions for commonly used utilities.</em>    </li>
     <li> <strong class="uidlink"><a href="googleapiclient.channel-module.html">googleapiclient.channel</a></strong>: <em class="summary">Channel notifications support.</em>    </li>
     <li> <strong class="uidlink"><a href="googleapiclient.discovery-module.html">googleapiclient.discovery</a></strong>: <em class="summary">Client for discovery based APIs.</em>    </li>
     <li> <strong class="uidlink"><a href="googleapiclient.discovery_cache-module.html">googleapiclient.discovery_cache</a></strong>: <em class="summary">Caching utility for the discovery document.</em>
@@ -102,7 +103,7 @@
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-    Generated by Epydoc 3.0.1 on Mon Jun  5 13:38:39 2017
+    Generated by Epydoc 3.0.1 on Fri Jun 14 13:09:01 2019
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