In Jinja2, how do you test if a variable is undefined?

Question

Converting from Django, I\'m used to doing something like this:

{% if not var1 %} {% endif %}

and having it work if I didn\'t put var1 into

Answer 1

From the Jinja2 template designer documentation:

{% if variable is defined %}
    value of variable: {{ variable }}
{% else %}
    variable is not defined
{% endif %}