My container is a flexbox, and contains 3 divs. How do I align one div to the left, one in the center, and one to the right?

Question

Basically, given a template like this:

<div class="container">
  <div class="item-one">
  </div>
  <div class="item-two">
  </div>
  <div class="item-three">
  </div>
</div>

Where class="container" is a flexbox:

.container {
  width: 1000px;
  height: 100px;
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: center;
}

How would you align the three items like this:

[ item-one item-two item-three]

I can't use floats since I am using flexbox, and the reason I am using flexbox is because item-two is dynamic and may have a varying width.

Thanks