title: Getting product variations from WC_Product_Variation
body: <p>I have a <code>WooCommerce</code> webshop, where T-Shirts are being sold. When a person looks at the cart, I'd like to give them the option to change sized on a T-Shirt. Currently, the dropdown menu i made looks like this:</p>
  
  <pre><code>&lt;?php
      if ( $item-&gt;is_type( 'variation' ) ){
  ?&gt;
  &lt;select name="" class="product-size"&gt;
  &lt;?php
      foreach ( $item-&gt;get_available_variations() as $variation ):
  ?&gt;
          &lt;option value=""&gt;test&lt;/option&gt;
  &lt;?php
      endforeach;
  ?&gt;
  &lt;/select&gt;
  &lt;?php
     }
  ? &gt;
  </code></pre>
  
  <p>However, this gives me the following error:</p>
  
  <pre><code>Fatal error: Uncaught Error: Call to undefined method WC_Product_Variation::get_available_variations()
  </code></pre>
  
  <p>So then it hit me; my <code>$item</code> variable, is already a variation. Is there a way to get the other variations for the same product?</p>
  
  <p>Thanks</p>