title: Syntax highlighting in Jekyll based on YAML variable
body: <p>When writing markdown with code to be read by Jekyll, you can enable syntax highlighting with</p>
  
  <pre><code>{% highlight python %}
  x = ('a', 1, False)
  {% endhighlight %}
  </code></pre>
  
  <p>However, this becomes a bit verbose if you constantly switch between code and text. Is it possible to introduce a YAML variable in the header, like</p>
  
  <pre><code>---
  layout: page
  title: "Syntax highlighting"
  tags : [python, jekyll]
  language: python
  ---
  </code></pre>
  
  <p>so that every code block on this page will be highlighted like python, but only needs to be indented, and not fenced off?</p>