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quoting attribute values is a hard habit to break
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Mark Pilgrim
@@ -14,7 +14,7 @@ mark{display:inline}
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<p id=level>Difficulty level: <span title=beginner>♦♦♦♢♢</span>
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<h1>XML</h1>
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<blockquote class=q>
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<p><span>❝</span> FIXME <span>❞</span><br>— FIXME
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<p><span>❝</span> In the archonship of Aristaechmus, Draco enacted his ordinances. <span>❞</span><br>— <a href="http://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus:text:1999.01.0046;query=chapter%3D%235;layout=;loc=3.1">Aristotle</a>
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</blockquote>
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<p id=toc>
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<h2 id=divingin>Diving In</h2>
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@@ -270,39 +270,67 @@ mark{display:inline}
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<pre class=screen>
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# continued from the previous example
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<samp class=p>>>> </samp><kbd>root.tag</kbd>
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<a><samp class=p>>>> </samp><kbd>root.tag</kbd> <span>①</span></a>
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<samp>'{http://www.w3.org/2005/Atom}feed'</samp>
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<samp class=p>>>> </samp><kbd>len(root)</kbd>
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<samp>9</kbd>
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<samp class=p>>>> </samp><kbd>for child in root:</kbd>
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<samp class=p>... </samp><kbd> print(child)</kbd>
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<a><samp class=p>>>> </samp><kbd>len(root)</kbd> <span>②</span></a>
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<samp>8</samp>
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<a><samp class=p>>>> </samp><kbd>for child in root:</kbd> <span>③</span></a>
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<a><samp class=p>... </samp><kbd> print(child)</kbd> <span>④</span></a>
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<samp class=p>... </samp>
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<samp><Element {http://www.w3.org/2005/Atom}title at e2b5d0>
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<Element {http://www.w3.org/2005/Atom}subtitle at e2b4e0>
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<Element {http://www.w3.org/2005/Atom}id at e2b6c0>
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<Element {http://www.w3.org/2005/Atom}updated at e2b6f0>
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<Element {http://www.w3.org/2005/Atom}link at e181b0>
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<Element {http://www.w3.org/2005/Atom}link at e2b4b0>
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<Element {http://www.w3.org/2005/Atom}entry at e2b720>
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<Element {http://www.w3.org/2005/Atom}entry at e2b510>
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<Element {http://www.w3.org/2005/Atom}entry at e2b750></samp></pre>
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<ol>
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<li>Continuing from the previous example, the root element is <code>{http://www.w3.org/2005/Atom}feed</code>.
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<li>The “length” of the root element is the number of child elements.
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<li>You can use the element itself as an iterator to loop through all of its child elements.
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<li>As you can see from the output, there are indeed 8 child elements: all of the feed-level metadata (<code>title</code>, <code>subtitle</code>, <code>id</code>, <code>updated</code>, and <code>link</code>) followed by the three <code>entry</code> elements.
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</ol>
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<p>You may have guessed this already, but I want to point it out explicitly: the list of child elements only includes <em>direct</em> children. Each of the <code>entry</code> elements contain their own children, but those are not included in the list. They would be included in the list of each <code>entry</code>’s children, but they are not included in the list of the <code>feed</code>’s children. There are ways to find elements no matter how deeply nested they are; we’ll look at two such ways later in this chapter.
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<h3 id=xml-attributes>Attributes Are Dictonaries</h3>
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<p>FIXME
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<p>XML isn’t just a collection of elements; each element can also have its own set of attributes. Once you have a reference to a specific element, you can easily get its attributes as a Python dictionary.
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<p>To refresh your memory, here is the first few lines of <code>feed.xml</code>, the XML document we’re working with.
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<pre><code><feed xmlns="http://www.w3.org/2005/Atom" xml:lang="en">
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<title>dive into mark</title>
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<subtitle>currently between addictions</subtitle>
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<id>tag:diveintomark.org,2001-07-29:/</id>
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<updated>2009-03-27T21:56:07Z</updated>
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<link rel="alternate" type="text/html" href="http://diveintomark.org/"/>
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<link rel="self" type="application/atom+xml" href="http://diveintomark.org/feed/"/>
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...</code></pre>
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<pre class=screen>
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>>> root.attrib
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{'{http://www.w3.org/XML/1998/namespace}lang': 'en'}
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>>> root[4]
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<Element {http://www.w3.org/2005/Atom}link at e181b0>
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>>> root[4].attrib
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{'href': 'http://diveintomark.org/', 'type': 'text/html', 'rel': 'alternate'}
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>>> root[3]
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<Element {http://www.w3.org/2005/Atom}updated at e2b4e0>
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>>> root[3].attrib
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{}
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</pre>
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<feed xmlns="http://www.w3.org/2005/Atom" xml:lang="en">
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FIXME
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# continuing from the previous example
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<a><samp class=p>>>> </samp><kbd>root.attrib</kbd> <span>①</span></a>
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<samp>{'{http://www.w3.org/XML/1998/namespace}lang': 'en'}</samp>
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<a><samp class=p>>>> </samp><kbd>root[4]</kbd> <span>②</span></a>
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<samp><Element {http://www.w3.org/2005/Atom}link at e181b0></samp>
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<a><samp class=p>>>> </samp><kbd>root[4].attrib</kbd> <span>③</span></a>
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<samp>{'href': 'http://diveintomark.org/',
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'type': 'text/html',
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'rel': 'alternate'}</samp>
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<a><samp class=p>>>> </samp><kbd>root[3]</kbd> <span>④</span></a>
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<samp><Element {http://www.w3.org/2005/Atom}updated at e2b4e0></samp>
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<a><samp class=p>>>> </samp><kbd>root[3].attrib</kbd> <span>⑤</span></a>
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<samp>{}</samp></pre>
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<ol>
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<li>The <code>attrib</code> property is a dictionary of the element’s attributes. The original markup here was <code><feed xmlns
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<li>
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<li>
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<li>
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<li>
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</ol>
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<h2 id=xml-find>Searching For Nodes Within An XML Document</h2>
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