title: Relational condition check in Django Rest Framework
body: <p>Hi I am trying to validate at least one of field is required in Django rest framework  json .</p>
  
  <p>Here is my serializer class </p>
  
  <pre><code>class WorkloadPutSerializer(serializers.Serializer):
  
      vdi = VdiSerializer(required = False)
      db = DbSerializer(required = False)
      vm= VmSerializer(required = False)
      pk = serializers.IntegerField(read_only=True)
  </code></pre>
  
  <p>I want to force  user to enter either <code>vdi</code>  or <code>vm</code>   or both .</p>
  
  <p>Is there any way to do validate this condition in django rest framework .Please help me out I am not able to  find out in Django rest Framework Documentation .</p>