code: public com.google.protobuf.ByteString
        getOverviewBytes() {
      java.lang.Object ref = overview_;
      if (ref instanceof java.lang.String) {
        com.google.protobuf.ByteString b = 
            com.google.protobuf.ByteString.copyFromUtf8(
                (java.lang.String) ref);
        overview_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }
docs: <pre>
  Declares a single overview page. For example:
  &lt;pre&gt;&lt;code&gt;documentation:
  summary: ...
  overview: &amp;#40;== include overview.md ==&amp;#41;
  &lt;/code&gt;&lt;/pre&gt;
  This is a shortcut for the following declaration (using pages style):
  &lt;pre&gt;&lt;code&gt;documentation:
  summary: ...
  pages:
  - name: Overview
  content: &amp;#40;== include overview.md ==&amp;#41;
  &lt;/code&gt;&lt;/pre&gt;
  Note: you cannot specify both `overview` field and `pages` field.
  </pre>
  
  <code>string overview = 2;</code>