You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mixcloud_onebox.rb
    path of file: ./repos/discourse/lib/onebox/engine
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

module Onebox
  module Engine
    class MixcloudOnebox
      include Engine
      include StandardEmbed

      matches_regexp(%r{^https?://www\.mixcloud\.com/})
      always_https
      requires_iframe_origins "https://www.mixcloud.com"

      def placeholder_html
        oembed = get_oembed

        <<-HTML
          <aside class="onebox mixcloud-preview">
            <article class="onebox-body">
              <img src="#{oembed.image}">
    
      def placeholder_html
        oembed = get_oembed

        <<-HTML
          <aside class="onebox mixcloud-preview">
            <article class="onebox-body">
              <img src="#{oembed.image}">
              <div class="video-icon"></div>
              <div class="mixcloud-text">
                <h3><a href="#{oembed.url}" target="_blank" rel="nofollow ugc noopener">#{oembed.title}</a></h3>
                <h4>#{oembed.author_name}</h4>
              </div>
            </article>
          </aside>
        HTML
      end