diff --git a/pdf/index_for_pdf.html b/pdf/index_for_pdf.html
index bdfa022..ce18771 100644
--- a/pdf/index_for_pdf.html
+++ b/pdf/index_for_pdf.html
@@ -6,7 +6,7 @@
 
 <div style="column-count: 3; width: 960px; page-break-inside: avoid">
 <h3 id="a">A</h3>
-<p><strong>abstract base classes, <a href="#abstractbaseclasses">4</a>, <a href="#collectionsabcsequence">19</a></strong><br>
+<p><strong>abstract base classes, <a href="#abstractbaseclasses">4</a>, <a href="#abcsequence">19</a></strong><br>
 <strong>all function, <a href="#anyall">11</a></strong><br>
 <strong>animation, <a href="#animation">40</a></strong><br>
 <strong>any function, <a href="#anyall">11</a></strong><br>
@@ -24,10 +24,10 @@
 <h3 id="c">C</h3>
 <p><strong>cache, <a href="#lrucache">13</a></strong><br>
 <strong>callable, <a href="#callable">17</a></strong><br>
-<strong>class, <a href="#type">4</a>, <a href="#class">14</a>-<a href="#collectionsabcsequence">19</a>, <a href="#metaprograming">31</a>-<a href="#metaclass">32</a></strong><br>
+<strong>class, <a href="#type">4</a>, <a href="#class">14</a>-<a href="#abcsequence">19</a>, <a href="#metaprograming">31</a>-<a href="#metaclass">32</a></strong><br>
 <strong>closure, <a href="#closure">12</a></strong><br>
 <strong>collection, <a href="#type">4</a>, <a href="#collection">18</a></strong><br>
-<strong>collections module, <a href="#counter">2</a>, <a href="#namedtuple">3</a>, <a href="#abstractbaseclasses">4</a>, <a href="#collectionsabcsequence">19</a>, <a href="#deque">29</a></strong><br>
+<strong>collections module, <a href="#counter">2</a>, <a href="#namedtuple">3</a>, <a href="#abstractbaseclasses">4</a>, <a href="#abcsequence">19</a>, <a href="#deque">29</a></strong><br>
 <strong>combinatorics, <a href="#combinatorics">8</a></strong><br>
 <strong>command line arguments, <a href="#commandlinearguments">22</a></strong><br>
 <strong>comparable, <a href="#comparable">16</a></strong><br>
@@ -44,7 +44,7 @@
 <strong>decorator, <a href="#decorator">13</a></strong><br>
 <strong>deques, <a href="#deque">29</a></strong><br>
 <strong>dictionaries, <a href="#dictionary">2</a>, <a href="#otheruses">11</a></strong><br>
-<strong>duck types, <a href="#ducktypes">16</a>-<a href="#collectionsabcsequence">19</a></strong>  </p>
+<strong>duck types, <a href="#ducktypes">16</a>-<a href="#abcsequence">19</a></strong>  </p>
 <h3 id="e">E</h3>
 <p><strong>enum module, <a href="#enum">19</a>-<a href="#inline-2">20</a></strong><br>
 <strong>enumerate function, <a href="#enumerate">3</a></strong><br>
@@ -121,7 +121,7 @@
 <strong>requests library, <a href="#scraping">35</a>, <a href="#test">36</a></strong>  </p>
 <h3 id="s">S</h3>
 <p><strong>scraping, <a href="#scraping">35</a>, <a href="#basicmariobrothersexample">43</a></strong><br>
-<strong>sequence, <a href="#type">4</a>, <a href="#sequence">18</a>, <a href="#collectionsabcsequence">19</a></strong><br>
+<strong>sequence, <a href="#type">4</a>, <a href="#sequence">18</a>, <a href="#abcsequence">19</a></strong><br>
 <strong>sets, <a href="#set">2</a>, <a href="#otheruses">11</a></strong><br>
 <strong>shell commands, <a href="#shellcommands">25</a></strong><br>
 <strong>sleep function, <a href="#progressbar">34</a></strong><br>