title: How to get field value in the Serializer
body: <p>I want to get <strong>id</strong> value passing in the serializer that is<br>
  <code>id = serializers.IntegerField(label='ID')</code> in the function to get the profile object </p>
  
  <p><strong>def profile_info(self, obj)</strong> </p>
  
  <blockquote>
    <p>But it giving the error <strong>id</strong> is <code>IntegerField</code> please pass the int or
    string</p>
  </blockquote>
  
  <p>Can Anybody tell me how to get values passed in <strong>id</strong> field thanks.  Down below is my serializer code</p>
  
  <pre><code>class UserSerializer(serializers.ModelSerializer):
      id = serializers.IntegerField(label='ID')
      # print ('dadddaaa ',serializers.data)
      profile = serializers.SerializerMethodField('profile_info')
      username = serializers.CharField()
      first_name = serializers.CharField()
      last_name = serializers.CharField()
      # Nazir = serializers.CharField()
      # profile = UsersSerializer(Profile.objects.get(User.objects.get(pk=serializers.data['id'])))
      def profile_info(self, obj): 
          # print ('selffff   ', serializers)
          prof_obj = Profile.objects.get(user=User.objects.get(pk=id))
          return {'id':prof_obj.id}
  </code></pre>