chore: regens API reference docs (#889)

diff --git a/docs/dyn/youtube_v3.activities.html b/docs/dyn/youtube_v3.activities.html
index f489f71..0db396b 100644
--- a/docs/dyn/youtube_v3.activities.html
+++ b/docs/dyn/youtube_v3.activities.html
@@ -75,7 +75,7 @@
 <h1><a href="youtube_v3.html">YouTube Data API</a> . <a href="youtube_v3.activities.html">activities</a></h1>
 <h2>Instance Methods</h2>
 <p class="toc_element">
-  <code><a href="#insert">insert(part, body)</a></code></p>
+  <code><a href="#insert">insert(part, body=None)</a></code></p>
 <p class="firstline">Posts a bulletin for a specific channel. (The user submitting the request must be authorized to act on the channel's behalf.)</p>
 <p class="toc_element">
   <code><a href="#list">list(part, pageToken=None, publishedBefore=None, channelId=None, mine=None, maxResults=None, regionCode=None, home=None, publishedAfter=None)</a></code></p>
@@ -85,14 +85,14 @@
 <p class="firstline">Retrieves the next page of results.</p>
 <h3>Method Details</h3>
 <div class="method">
-    <code class="details" id="insert">insert(part, body)</code>
+    <code class="details" id="insert">insert(part, body=None)</code>
   <pre>Posts a bulletin for a specific channel. (The user submitting the request must be authorized to act on the channel's behalf.)
 
 Note: Even though an activity resource can contain information about actions like a user rating a video or marking a video as a favorite, you need to use other API methods to generate those activity resources. For example, you would use the API's videos.rate() method to rate a video and the playlistItems.insert() method to mark a video as a favorite.
 
 Args:
   part: string, The part parameter serves two purposes in this operation. It identifies the properties that the write operation will set as well as the properties that the API response will include. (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # An activity resource contains information about an action that a particular channel, or user, has taken on YouTube.The actions reported in activity feeds include rating a video, sharing a video, marking a video as a favorite, commenting on a video, uploading a video, and so forth. Each activity resource identifies the type of action, the channel associated with the action, and the resource(s) associated with the action, such as the video that was rated or uploaded.