title: How to read output_content from azurerm_resource_group_template_deployment
body: <p>I have defined an azurerm_resource_group_template_deployment <strong>my_rm</strong> which has ARM template source:</p>
  <pre><code>{
    ...
    &quot;parameters&quot;: {...  }, 
    &quot;resources&quot;: [ ...  ],
    &quot;outputs&quot;: {
      &quot;db_name&quot;: {
        &quot;type&quot;: &quot;string&quot;,
        &quot;value&quot;: &quot;test_value&quot;
      } 
    }
  }
  </code></pre>
  <p>I would like to use this output in terraform, like:</p>
  <pre><code>output &quot;db_name&quot; {
    value = azurerm_resource_group_template_deployment.my_rm.output_content[&quot;db_name&quot;]
  }
  </code></pre>
  <p>Unfortunately above definition returns empty value.</p>
  <p>What is the correct way to define the output in terraform?</p>