Jinja2 is a template engine written in pure Python. It provides a Django
 inspired non-XML syntax but supports inline expressions and an optional
 sandboxed environment.
 .
 The key-features are:
  * Configurable syntax. If you are generating LaTeX or other formats with
    Jinja2 you can change the delimiters to something that integrates better
    into the LaTeX markup.
  * Fast. While performance is not the primarily target of Jinja2 it’s
    surprisingly fast. The overhead compared to regular Python code was reduced
    to the very minimum.
  * Easy to debug. Jinja2 integrates directly into the Python traceback system
    which allows you to debug Jinja2 templates with regular Python debugging
    helpers.
  * Secure. It’s possible to evaluate untrusted template code if the optional
    sandbox is enabled. This allows Jinja2 to be used as templating language
    for applications where users may modify the template design.