python ternary in jinja2 gives TemplateSyntaxError: tag name expected

You used "{% %}" which wants to get a tag like if, endif etc. If you just want to execute a piece of python code, like your ternary expression, you should use double braces like so

{{ 'row-story-published' if  person.storyPublished  else ' ' }}

Template language is different than Python, so has different syntax. You cannot use Python's idiomatic syntax in templates.

<tr class="row-person {% if  person.storyPublished %} row-story-published {% endif %}" >