Fix context deprecation in latest django

src/common/serializers.py

@@ -2,11 +2,10 @@ from rest_framework import compat
 
 
 class CurrentUserProfileDefault(object):
-    def set_context(self, serializer_field):
-        self.user = serializer_field.context['request'].user
+    requires_context = True
 
-    def __call__(self):
-        return self.user.profile
+    def __call__(self, serializer_field):
+        return serializer_field.context['request'].user.profile
 
     def __repr__(self):
         return compat.unicode_to_repr('%s()' % self.__class__.__name__)