  
  
  class DeserializationError(Exception):
      """Something bad happened during deserialization."""
      pass
  
  
  class Serializer(object):
      """
      Abstract serializer base class.
 
</s> remove     ]
 </s> add     ],
    "meta_data": []
    @classmethod
    def WithData(cls, original_exc, model, fk, field_value):
        """
        Factory method for creating a deserialization error which has a more
        explanatory messsage.
        """
        return cls("%s: (%s:pk=%s) field_value was '%s'" % (original_exc, model, fk, field_value))
  
  
  class DeserializationError(Exception):
      """Something bad happened during deserialization."""
    @classmethod
    def WithData(cls, original_exc, model, fk, field_value):
        """
        Factory method for creating a deserialization error which has a more
        explanatory messsage.
        """
        return cls("%s: (%s:pk=%s) field_value was '%s'" % (original_exc, model, fk, field_value))
  
  
  class Serializer(object):
      """
      Abstract serializer base class.
keep keep keep keep replace keep keep keep keep keep
 Fixed #19820 -- Added more helpful error messages to Python deserializer. 
django/core/serializers/base.py