added 20th Python tip

Author: learnbyexample

Diff for: README.md

@@ -61,6 +61,7 @@ I'm addicted to reading fantasy/sci-fi books, so I have a [blog](https://learnby
 
 ## Tips
 
+* [Python tip 20: saving and loading json](https://learnbyexample.github.io/tips/python-tip-20/)
 * [Vim tip 18: moving within long lines](https://learnbyexample.github.io/tips/vim-tip-18/)
 * [CLI tip 19: extended globs](https://learnbyexample.github.io/tips/cli-tip-19/)
 * [Python tip 19: manipulating string case](https://learnbyexample.github.io/tips/python-tip-19/)

Diff for: atom.xml

@@ -5,8 +5,45 @@
 	<link href="https://learnbyexample.github.io/atom.xml" rel="self" type="application/atom+xml"/>
   <link href="https://learnbyexample.github.io"/>
 	<generator uri="https://www.getzola.org/">Zola</generator>
-	<updated>2022-11-29T00:00:00+00:00</updated>
+	<updated>2022-12-07T00:00:00+00:00</updated>
 	<id>https://learnbyexample.github.io/atom.xml</id>
+	<entry xml:lang="en">
+		<title>Python tip 20: saving and loading json</title>
+		<published>2022-12-07T00:00:00+00:00</published>
+		<updated>2022-12-07T00:00:00+00:00</updated>
+		<link rel="alternate" href="https://learnbyexample.github.io/tips/python-tip-20/" type="text/html"/>
+		<id>https://learnbyexample.github.io/tips/python-tip-20/</id>
+		<content type="html">&lt;p&gt;JSON (JavaScript Object Notation) is one of the ways you can store and retrieve data necessary for functioning of an application. For example, my projects &lt;a href=&quot;https:&#x2F;&#x2F;github.com&#x2F;learnbyexample&#x2F;py_regular_expressions&#x2F;tree&#x2F;master&#x2F;interactive_exercises&quot;&gt;Python regex exercises&lt;&#x2F;a&gt; and &lt;a href=&quot;https:&#x2F;&#x2F;github.com&#x2F;learnbyexample&#x2F;TUI-apps&#x2F;blob&#x2F;main&#x2F;CLI-Exercises&quot;&gt;Linux CLI text processing exercises&lt;&#x2F;a&gt; need to load questions and save user progress. You might wonder why not just a plain text file? I needed &lt;code&gt;dict&lt;&#x2F;code&gt; in the code anyway and JSON offered seamless transition. Also, this arrangement avoided having to write extra code and test it for potential parsing issues.&lt;&#x2F;p&gt;
+&lt;p&gt;The &lt;code&gt;json&lt;&#x2F;code&gt; builtin module is handy for such purposes. Here&#x27;s an example of saving a &lt;code&gt;dict&lt;&#x2F;code&gt; object:&lt;&#x2F;p&gt;
+&lt;pre data-lang=&quot;python&quot; style=&quot;background-color:#f5f5f5;color:#1f1f1f;&quot; class=&quot;language-python &quot;&gt;&lt;code class=&quot;language-python&quot; data-lang=&quot;python&quot;&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;&amp;gt;&amp;gt;&amp;gt; import &lt;&#x2F;span&gt;&lt;span&gt;json
+&lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;&amp;gt;&amp;gt;&amp;gt; &lt;&#x2F;span&gt;&lt;span&gt;marks &lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;= &lt;&#x2F;span&gt;&lt;span&gt;{&lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;Rahul&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;86&lt;&#x2F;span&gt;&lt;span&gt;, &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;Ravi&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;92&lt;&#x2F;span&gt;&lt;span&gt;, &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;Rohit&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;75&lt;&#x2F;span&gt;&lt;span&gt;, &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;Rajan&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;79&lt;&#x2F;span&gt;&lt;span&gt;}
+&lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;&amp;gt;&amp;gt;&amp;gt; with &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b39f04;&quot;&gt;open&lt;&#x2F;span&gt;&lt;span&gt;(&lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;marks.json&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;, &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;w&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;) &lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;as &lt;&#x2F;span&gt;&lt;span&gt;f:
+&lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;...     &lt;&#x2F;span&gt;&lt;span&gt;json.&lt;&#x2F;span&gt;&lt;span style=&quot;color:#5597d6;&quot;&gt;dump&lt;&#x2F;span&gt;&lt;span&gt;(marks, f, &lt;&#x2F;span&gt;&lt;span style=&quot;color:#5597d6;&quot;&gt;indent&lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;=&lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;4&lt;&#x2F;span&gt;&lt;span&gt;)
+&lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;... 
+&lt;&#x2F;span&gt;&lt;&#x2F;code&gt;&lt;&#x2F;pre&gt;
+&lt;p&gt;In the above example, &lt;code&gt;indent&lt;&#x2F;code&gt; is used for pretty printing. Here&#x27;s how the file looks like:&lt;&#x2F;p&gt;
+&lt;pre data-lang=&quot;ruby&quot; style=&quot;background-color:#f5f5f5;color:#1f1f1f;&quot; class=&quot;language-ruby &quot;&gt;&lt;code class=&quot;language-ruby&quot; data-lang=&quot;ruby&quot;&gt;&lt;span&gt;$ cat marks.json
+&lt;&#x2F;span&gt;&lt;span&gt;{
+&lt;&#x2F;span&gt;&lt;span&gt;    &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;quot;Rahul&amp;quot;&lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;86&lt;&#x2F;span&gt;&lt;span&gt;,
+&lt;&#x2F;span&gt;&lt;span&gt;    &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;quot;Ravi&amp;quot;&lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;92&lt;&#x2F;span&gt;&lt;span&gt;,
+&lt;&#x2F;span&gt;&lt;span&gt;    &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;quot;Rohit&amp;quot;&lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;75&lt;&#x2F;span&gt;&lt;span&gt;,
+&lt;&#x2F;span&gt;&lt;span&gt;    &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;quot;Rajan&amp;quot;&lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;79
+&lt;&#x2F;span&gt;&lt;span&gt;}
+&lt;&#x2F;span&gt;&lt;&#x2F;code&gt;&lt;&#x2F;pre&gt;
+&lt;p&gt;And here&#x27;s an example of loading a JSON file:&lt;&#x2F;p&gt;
+&lt;pre data-lang=&quot;python&quot; style=&quot;background-color:#f5f5f5;color:#1f1f1f;&quot; class=&quot;language-python &quot;&gt;&lt;code class=&quot;language-python&quot; data-lang=&quot;python&quot;&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;&amp;gt;&amp;gt;&amp;gt; with &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b39f04;&quot;&gt;open&lt;&#x2F;span&gt;&lt;span&gt;(&lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;marks.json&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;) &lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;as &lt;&#x2F;span&gt;&lt;span&gt;f:
+&lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;...     &lt;&#x2F;span&gt;&lt;span&gt;marks &lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;= &lt;&#x2F;span&gt;&lt;span&gt;json.&lt;&#x2F;span&gt;&lt;span style=&quot;color:#5597d6;&quot;&gt;load&lt;&#x2F;span&gt;&lt;span&gt;(f)
+&lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;... 
+&lt;&#x2F;span&gt;&lt;span style=&quot;color:#72ab00;&quot;&gt;&amp;gt;&amp;gt;&amp;gt; &lt;&#x2F;span&gt;&lt;span&gt;marks
+&lt;&#x2F;span&gt;&lt;span&gt;{&lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;Rahul&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;86&lt;&#x2F;span&gt;&lt;span&gt;, &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;Ravi&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;92&lt;&#x2F;span&gt;&lt;span&gt;, &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;Rohit&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;75&lt;&#x2F;span&gt;&lt;span&gt;, &lt;&#x2F;span&gt;&lt;span style=&quot;color:#d07711;&quot;&gt;&amp;#39;Rajan&amp;#39;&lt;&#x2F;span&gt;&lt;span&gt;: &lt;&#x2F;span&gt;&lt;span style=&quot;color:#b3933a;&quot;&gt;79&lt;&#x2F;span&gt;&lt;span&gt;}
+&lt;&#x2F;span&gt;&lt;&#x2F;code&gt;&lt;&#x2F;pre&gt;
+&lt;p&gt;&lt;img src=&quot;&#x2F;images&#x2F;info.svg&quot; alt=&quot;info&quot; &#x2F;&gt; See &lt;a href=&quot;https:&#x2F;&#x2F;docs.python.org&#x2F;3&#x2F;library&#x2F;json.html&quot;&gt;docs.python: json&lt;&#x2F;a&gt; for documentation, more examples, other methods, caveats and so on.&lt;&#x2F;p&gt;
+&lt;p&gt;&lt;strong&gt;Video demo&lt;&#x2F;strong&gt;:&lt;&#x2F;p&gt;
+&lt;p align=&quot;center&quot;&gt;&lt;iframe width=&quot;560&quot; height=&quot;315&quot; loading=&quot;lazy&quot; src=&quot;https:&#x2F;&#x2F;www.youtube.com&#x2F;embed&#x2F;Fd28UTqcU3k&quot; title=&quot;YouTube video player&quot; frameborder=&quot;0&quot; allow=&quot;accelerometer; clipboard-write; encrypted-media; gyroscope; picture-in-picture&quot; allowfullscreen&gt;&lt;&#x2F;iframe&gt;&lt;&#x2F;p&gt;
+&lt;br&gt;
+&lt;p&gt;&lt;img src=&quot;&#x2F;images&#x2F;info.svg&quot; alt=&quot;info&quot; &#x2F;&gt; See also my &lt;a href=&quot;https:&#x2F;&#x2F;github.com&#x2F;learnbyexample&#x2F;100_page_python_intro&quot;&gt;100 Page Python Intro&lt;&#x2F;a&gt; ebook.&lt;&#x2F;p&gt;
+</content>
+	</entry>
 	<entry xml:lang="en">
 		<title>Vim tip 18: moving within long lines</title>
 		<published>2022-11-29T00:00:00+00:00</published>

Diff for: sitemap.xml

@@ -524,6 +524,10 @@
         <loc>https://learnbyexample.github.io/tips/python-tip-2/</loc>
         <lastmod>2022-05-16</lastmod>
     </url>
+    <url>
+        <loc>https://learnbyexample.github.io/tips/python-tip-20/</loc>
+        <lastmod>2022-12-07</lastmod>
+    </url>
     <url>
         <loc>https://learnbyexample.github.io/tips/python-tip-3/</loc>
         <lastmod>2022-05-16</lastmod>