Jinja2 template variable if None Object set a default value

Question

How to make a variable in Jijna2 default to "" if object is None instead of doing something like this?

{% if p %}   
    {{ p.User['first_name']}}
{% else %}
    NONE
{%endif %}

So if object p isNone. I want to default the values of p (first_name and last_name) to "". Basically:

nvl(p.User[first_name'], "")

Error receiving:

Error: jinja2.exceptions.UndefinedError
UndefinedError: 'None' has no attribute 'User'

Answer 1

Use the none test (not to be confused with Python's None object!):

{% if p is not none %}   
    {{ p.User['first_name'] }}
{% else %}
    NONE
{% endif %}

or:

{{ p.User['first_name'] if p is not none else 'NONE' }}

or if you need an empty string:

{{ p.User['first_name'] if p is not none }}