这个是哪个字段？怎么取到呢

<div class="left-nav"><span>热门话题</span></div>
        <div class="rmht-list">
           [@cms_content_list typeId='2' count='5' orderBy='9' channelId='75' channelOption='1']
             [#list tag_list as a]
          <div [#if a_index<1]class="item first"[#else]class="item"[/#if]>
            <a href="${a.url}" target="_blank" class="title">[@text_cut s=a.title len='19' append='...' /]</a>
            [#if a_index<1]<div class="first-des clearfix"><a href="${a.url}" target="_blank"><img src="${a.typeImg!}"></a><span>[@text_cut s=a.description! len='34' append='...' /]</span></div>[/#if]
          </div>
          [/#list]
   [/@cms_content_list]
        </div>

<img src="${a.typeImg!}"调用的类型图