<p>The <a href="https://www.twilio.com/blog/tag/python">Python projects tag</a> on the

Twilio blog is constantly updated with fun tutorials you can build to

learn Python, such as the

<a href="https://www.twilio.com/blog/2015/11/international-space-station-notifications-with-python-redis-queue-and-twilio-copilot.html">International Space Station Tracker with Flask and Redis-Queue</a>,

<a href="https://www.twilio.com/blog/2014/11/choose-your-own-adventure-presentations-with-reveal-js-python-and-websockets.html">Choose Your Own Adventures Presentations using Flask and WebSockets</a>

and <a href="https://www.twilio.com/blog/2015/11/getting-started-with-opencv-and-python-featuring-the-martian-2.html">Martianify Photos with OpenCV</a>.</p>

<h1>Template Engines</h1>

<p>Template engines process template files, which provide an intermediate format

between your Python code and a desired output format, such as HTML or PDF.</p>

<h2>Why are template engines important?</h2>

<p>Template engines allow developers to generate a desired content type, such

as HTML, while using some of the data and programming constructs such as

conditionals and for loops to manipulate the output. Template files that are

created by developers and then processed by the template engine consist of

prewritten markup and template tag blocks where data is inserted.</p>

<p>For example, look at the first ten source lines of HTML of this webpage:</p>

<div class="highlight"><pre><span class="cp">&lt;!DOCTYPE html&gt;</span>

<span class="nt">&lt;html</span> <span class="na">lang=</span><span class="s">&quot;en&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;head&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">http-equiv=</span><span class="s">&quot;Content-Type&quot;</span> <span class="na">content=</span><span class="s">&quot;text/html; charset=UTF-8&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">charset=</span><span class="s">&quot;utf-8&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">http-equiv=</span><span class="s">&quot;X-UA-Compatible&quot;</span> <span class="na">content=</span><span class="s">&quot;IE=edge&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">name=</span><span class="s">&quot;viewport&quot;</span> <span class="na">content=</span><span class="s">&quot;width=device-width, initial-scale=1.0&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">name=</span><span class="s">&quot;author&quot;</span> <span class="na">content=</span><span class="s">&quot;Matt Makai&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">name=</span><span class="s">&quot;description&quot;</span> <span class="na">content=</span><span class="s">&quot;Template engines provide programmatic output of formatted content such as HTML, XML or PDF.&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;link</span> <span class="na">rel=</span><span class="s">&quot;shortcut icon&quot;</span> <span class="na">href=</span><span class="s">&quot;//static.fullstackpython.com/fsp-fav.png&quot;</span><span class="nt">&gt;</span>

<p>Every one of the HTML lines above is standard for each page on Full Stack Python,

with the exception of the <code>&lt;meta name="description"...</code> line which provides

a unique short description of what the individual page contains.</p>

<p>The <a href="https://github.com/makaimc/fullstackpython.com/blob/gh-pages/source/theme/templates/base.html">base.html Jinja template</a> used to generate Full Stack Python

allows every page on Full Stack Python to have consistent HTML but

dynamically generate the pieces that should change between pages when

the <a href="/static-site-generator.html">static site generator</a> executes. The below

code from the <code>base.html</code> template shows that the meta description is up to child

templates to create.</p>

<div class="highlight"><pre><span class="cp">&lt;!DOCTYPE html&gt;</span>

<span class="nt">&lt;html</span> <span class="na">lang=</span><span class="s">&quot;en&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;head&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">http-equiv=</span><span class="s">&quot;Content-Type&quot;</span> <span class="na">content=</span><span class="s">&quot;text/html; charset=UTF-8&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">charset=</span><span class="s">&quot;utf-8&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">http-equiv=</span><span class="s">&quot;X-UA-Compatible&quot;</span> <span class="na">content=</span><span class="s">&quot;IE=edge&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">name=</span><span class="s">&quot;viewport&quot;</span> <span class="na">content=</span><span class="s">&quot;width=device-width, initial-scale=1.0&quot;</span><span class="nt">&gt;</span>

<span class="nt">&lt;meta</span> <span class="na">name=</span><span class="s">&quot;author&quot;</span> <span class="na">content=</span><span class="s">&quot;Matt Makai&quot;</span><span class="nt">&gt;</span>

<span class="cp">{%</span> <span class="k">block</span> <span class="nv">meta_header</span> <span class="cp">%}{%</span> <span class="k">endblock</span> <span class="cp">%}</span>

<span class="nt">&lt;link</span> <span class="na">rel=</span><span class="s">&quot;shortcut icon&quot;</span> <span class="na">href=</span><span class="s">&quot;//static.fullstackpython.com/fsp-fav.png&quot;</span><span class="nt">&gt;</span>

<p>In a typical <a href="/wsgi-servers.html">WSGI application</a>, the template engine would

generate the HTML output response when an HTTP request comes in for a

particular URL. </p>

<h2>Python template engines</h2>

<p>There are several popular Python template engines. Template engines have to

walk the spectrum between allowing arbitrary code execution and granting only

a limited set of capabilities via template tags.</p>

<h3>Jinja</h3>

<p><a href="http://jinja.pocoo.org/">Jinja</a>, also known as "Jinja2" is a popular Python

template engine written as an independent open source project, unlike some

template engines that are provided as part of a larger web framework.</p>

<p>Major Python open source applications such as the

<a href="/configuration-management.html">configuration management</a> tools Ansible

and <a href="https://github.com/saltstack/salt">SaltStack</a>

as well as the <a href="/static-site-generator.html">static site generator</a> Pelican use

the Jinja template engine by default for generating output files.</p>

<h3>Django templating</h3>

<p>Django comes with its

<a href="https://docs.djangoproject.com/en/dev/topics/templates/">own template engine</a>

in addition to supporting (as of Django 1.9) drop-in replacement with other

template engines such as Jinja.</p>

<h3>Mako</h3>

<p><a href="http://www.makotemplates.org/">Mako</a> is the default templating engine for

the <a href="/pyramid.html">Pyramid web framework</a> and has wide support as a replacement

template engine for many <a href="/other-web-frameworks.html">other web frameworks</a>.</p>

<h3>Template engine resources</h3>

<p><a href="http://aosabook.org/en/500L/a-template-engine.html">A template engine in 500 lines or less</a>

is an article by <a href="http://nedbatchelder.com/">Ned Batchelder</a> provides a<br />

template engine in 252 lines of Python that can be used to understand how

template engines work under the cover.</p>

<p><a href="https://realpython.com/blog/python/primer-on-jinja-templating/">A Primer on Jinja Templating</a>

shows how to use the major parts of this fantastic template engine.</p>

<p><a href="http://agiliq.com/blog/2015/08/template-fragment-caching-gotchas/">Template fragment gotchas</a>

is a collection of situations that can trip up a developer or designer when

working with templates.</p>

<a href="/template-engines.html" class="list-group-item smaller-item " style='font-family: "Helvetica Neue",sans-serif;'>Template Engines</a>

<a href="/template-engines.html" class="list-group-item smaller-item " style='font-family: "Helvetica Neue",sans-serif;'>Template Engines</a>

<a href="/template-engines.html" class="list-group-item smaller-item " style='font-family: "Helvetica Neue",sans-serif;'>Template Engines</a>

<a href="/template-engines.html" class="list-group-item smaller-item " style='font-family: "Helvetica Neue",sans-serif;'>Template Engines</a>

<p>The <a href="https://www.twilio.com/blog/tag/python">Python projects tag</a> on the

Twilio blog is constantly updated with fun tutorials you can build to

learn Python, such as the

<a href="https://www.twilio.com/blog/2015/11/international-space-station-notifications-with-python-redis-queue-and-twilio-copilot.html">International Space Station Tracker with Flask and Redis-Queue</a>,

<a href="https://www.twilio.com/blog/2014/11/choose-your-own-adventure-presentations-with-reveal-js-python-and-websockets.html">Choose Your Own Adventures Presentations using Flask and WebSockets</a>

and <a href="https://www.twilio.com/blog/2015/11/getting-started-with-opencv-and-python-featuring-the-martian-2.html">Martianify Photos with OpenCV</a>.</p>

<a href="/template-engines.html" class="list-group-item smaller-item " style='font-family: "Helvetica Neue",sans-serif;'>Template Engines</a>

<a href="/template-engines.html" class="list-group-item smaller-item " style='font-family: "Helvetica Neue",sans-serif;'>Template Engines</a>

<a href="/template-engines.html" class="list-group-item smaller-item " style='font-family: "Helvetica Neue",sans-serif;'>Template Engines</a>