title: In Woocommerce, how to use a legacy API instead of the latest version?
body: <p>In Woocommerce, how to use a legacy API version within another plugin code ?</p>
  
  <p>Currently, the newest API version of Woocommerce is loaded, thus when using WC_API_Server, it uses the latest one, and not a legacy one (version <strong>3</strong> needed) :</p>
  
  <pre><code>calling the class LMB_API_Server extends WC_API_Server 
  </code></pre>
  
  <p>I cannot change the Woocommerce plugin, nor its version - ideally, all I should be able to do is within the third party plugin that I develop.</p>
  
  <p>In the woocommerce folder :</p>
  
  <pre><code>includes\
   api\
    *manyPHPfileofcurrentVersion*
    ...
    legacy\
     v1\ 
     v2\ 
     v3\
       *oldPHPfilesOfAPInneded*
  </code></pre>
  
  <p><em>Note</em> : Woocommerce is a plugin for wordpress - and the API is inside this plugin. (even if the latest API uses wordpress' API itself)</p>
  
  <p><em>Update</em> : Unlike usual, here we need to use the API from the wordpress instance perspective - we would like to extend some of woocomerce methods located in the API. We therefore <strong>do not want to <em>consume</em> the API, but to <em>provide</em> an extended one.</strong></p>