Maybe for better readability I should rewrite this to:
````python
        markup = """
<div class="range-container">
    <div class="range-row">
        {0} &nbsp; <span id="slider_value"></span>
    </div>
    <div class="steps">
        <span style="left: 0%">0</span>
        <span style="left: 25%">15</span>
        <span style="left: 50%">30</span>
        <span style="left: 75%">45</span>
        <span style="left: 100%">60</span>
    </div>
</div>""".format(super(RangeInput, self).render(name, value, attrs))
````