title: How to render default value in ant design checkbox using boolean?
body: <p>I am trying to render a checkbox default value using ant-design.</p>
  
  <p>Here is the data I want to render </p>
  
  <pre><code>plainOptions: [
      {
          name: "apple",
          is_enabled: "true",
      },
      {
          name: "orange",
          is_enabled: "true"
      },
      {
          name: "banana",
          is_enabled: "true"      
      },
      {
          name: "grape",
          is_enabled: "false",
      },
  ]
  </code></pre>
  
  <p>And here is the component : </p>
  
  <pre><code>                    &lt;FormItemRow&gt;
                          &lt;Col span={24} style={colStyle}&gt;
                              &lt;FormItem label={'fruits'} colon={ false } style={{ marginBottom: 0 }}&gt; 
                                  &lt;CheckboxGroup options={plainOptions} defaultValue={['true']}&gt;
                                      {plainOptions.map(option =&gt; {
                                          return (
                                              &lt;Checkbox key={option.label}&gt;{option.label}&lt;/Checkbox&gt;
                                          )
                                      })}
                                  &lt;/CheckboxGroup&gt;
                              &lt;/FormItem&gt;
                          &lt;/Col&gt;
                          &lt;/FormItemRow&gt;
  </code></pre>
  
  <p>I get the result I want to see but the problem of using <strong>defaultValue</strong> inside of <strong>CheckboxGroup</strong> component is I get warning saying </p>
  
  <pre><code>Warning: Encountered two children with the same key, `true`. Keys should be unique so that components maintain their identity across updates. Non-unique keys may cause children to be duplicated and/or omitted — the behavior is unsupported and could change in a future version.
  </code></pre>
  
  <p>Seems like defaultValue works as just like <strong>key</strong> .</p>
  
  <p>I also added <strong>checked</strong> inside of <strong>Check</strong> component and assigned boolean value but it does not work either.</p>
  
  <p>How can I safely render a default value inside of checkbox without warning sign?</p>