Determine empty template variable in Django

Just use {% if narratives.narrative_text %}, I think. It will use Python's implicit false, which applies for empty strings, empty arrays, empty dicts, None, False, 0 etc..

Pipe through length and do your test against that value.

{% if narratives.narrative_text|length > 0 %}
    {{ narratives.narrative_text }}
{% else %}
    None
{% endif %}