beflask/app/templates/index.html

{% extends "base.html" %}
{% block content %}
    {% if benchmarks %}
        {% include "_benchmarks.html" %}
    {% else %}
        <img src="{{ url_for('static', filename='img/robert-lukeman-_RBcxo9AU-U-unsplash.jpg') }}"
             class="img-fluid"
             alt="image robert lukeman">
    {% endif %}
{% endblock %}