diff --git a/README.md b/README.md
index 4f44d1b..3cb06d9 100644
--- a/README.md
+++ b/README.md
@@ -1429,7 +1429,7 @@ value = args.<name>
 
 Open
 ----
-**Opens a file and returns a corresponding file object.**
+**Opens a file and returns a corresponding file object or raises 'FileNotFoundError'.**
 
 ```python
 <file> = open('<path>', mode='r', encoding=None, newline=None)
diff --git a/index.html b/index.html
index bb91ed6..3b4134c 100644
--- a/index.html
+++ b/index.html
@@ -1307,7 +1307,7 @@ value = args.&lt;name&gt;
 <li><strong>Use <code class="python hljs"><span class="hljs-string">'type=FileType(&lt;mode&gt;)'</span></code> for files.</strong></li>
 </ul>
 <h2 id="open"><a href="#open" name="open">#</a>Open</h2>
-<p><strong>Opens a file and returns a corresponding file object.</strong></p>
+<p><strong>Opens a file and returns a corresponding file object or raises 'FileNotFoundError'.</strong></p>
 <pre><code class="python language-python hljs">&lt;file&gt; = open(<span class="hljs-string">'&lt;path&gt;'</span>, mode=<span class="hljs-string">'r'</span>, encoding=<span class="hljs-keyword">None</span>, newline=<span class="hljs-keyword">None</span>)
 </code></pre>
 <ul>