title: How to validate an object with a key inside it in Yup Validation
body: <p>This is a snippet in my React application using Formik.</p>
  
  <p>My initial value is </p>
  
  <pre><code>initialValues: {
      country: { label: '', value: '' }
  }
  </code></pre>
  
  <p>My field input is <code>country</code> which is a <code>Select</code> option and its value when selected will be as</p>
  
  <pre><code>country: { label: 'India', value: 'India' }
  </code></pre>
  
  <p>My required <code>error</code> object when a <code>country</code> is not selected should be </p>
  
  <pre><code>{ country: "Please select a country" }
  </code></pre>
  
  <p>How can I add a yup validation to get my required error when a country is not selected, or in other means when <code>country.value === ''</code>?</p>
  
  <p>I wrote a validation like this</p>
  
  <pre><code>country: yup.object().shape({
          value: yup
              .string()
              .label('Country')
              .required("Please select a country"),
  })
  </code></pre>
  
  <p>which is wrong and this gives the error object as <code>country: { value: "Please select a country" }</code> which is not as my requirement.</p>
  
  <p>What changes should I do here?</p>