# Buggy code
def _DeserializeAttributeContainer(self, container_type, serialized_data):
    """Deserializes an attribute container.

    Args:
      container_type (str): attribute container type.
      serialized_data (bytes): serialized attribute container data.

    Returns:
      AttributeContainer: attribute container or None.

    Raises:
      IOError: if the serialized data cannot be decoded.
      OSError: if the serialized data cannot be decoded.
    """
    if not serialized_data:
        return None

    if self._serializers_profiler:
        self._serializers_profiler.StartTiming(container_type)

    try:
        serialized_string = serialized_data.decode("utf-8")
    except UnicodeDecodeError as exception:
        raise IOError("Unable to decode serialized data: {0!s}".format(exception))
    attribute_container = self._serializer.ReadSerialized(serialized_string)

    if self._serializers_profiler:
        self._serializers_profiler.StopTiming(container_type)

    return attribute_container


# Traceback (ValueError)
Traceback (most recent call last):
File "plaso/tools/log2timeline.py", line 97, in <module>
if not Main():
File "plaso/tools/log2timeline.py", line 72, in Main
tool.ExtractEventsFromSources()
File "plaso/plaso/cli/log2timeline_tool.py", line 448, in ExtractEventsFromSources
worker_memory_limit=self._worker_memory_limit)
File "plaso/plaso/multi_processing/task_engine.py", line 812, in ProcessSources
self._ProcessSources(source_path_specs, storage_writer)
File "plaso/plaso/multi_processing/task_engine.py", line 343, in _ProcessSources
self._ScheduleTasks(storage_writer)
File "plaso/plaso/multi_processing/task_engine.py", line 449, in _ScheduleTasks
self._MergeTaskStorage(storage_writer)
File "plaso/plaso/multi_processing/task_engine.py", line 256, in _MergeTaskStorage
maximum_number_of_containers=self._MAXIMUM_NUMBER_OF_CONTAINERS)
File "plaso/plaso/storage/sqlite/merge_reader.py", line 278, in MergeAttributeContainers
self._active_container_type, serialized_data)
File "plaso/plaso/storage/interface.py", line 600, in _DeserializeAttributeContainer
attribute_container = self._serializer.ReadSerialized(serialized_string)
File "plaso/plaso/serializer/json_serializer.py", line 404, in ReadSerialized
return cls.ReadSerializedDict(json_dict)
File "plaso/plaso/serializer/json_serializer.py", line 423, in ReadSerializedDict
json_object = cls._ConvertDictToObject(json_dict)
File "plaso/plaso/serializer/json_serializer.py", line 252, in _ConvertDictToObject
'supported.').format(attribute_name))
ValueError: Event data attribute value: return_value of type dict is not supported.

# Fixed code
def _DeserializeAttributeContainer(self, container_type, serialized_data):
    """Deserializes an attribute container.

    Args:
      container_type (str): attribute container type.
      serialized_data (bytes): serialized attribute container data.

    Returns:
      AttributeContainer: attribute container or None.

    Raises:
      IOError: if the serialized data cannot be decoded.
      OSError: if the serialized data cannot be decoded.
    """
    if not serialized_data:
        return None

    if self._serializers_profiler:
        self._serializers_profiler.StartTiming(container_type)

    try:
        serialized_string = serialized_data.decode("utf-8")
        attribute_container = self._serializer.ReadSerialized(serialized_string)

    except UnicodeDecodeError as exception:
        raise IOError("Unable to decode serialized data: {0!s}".format(exception))

    except (ValueError, TypeError) as exception:
        # TODO: consider re-reading attribute container with error correction.
        raise IOError("Unable to read serialized data: {0!s}".format(exception))

    finally:
        if self._serializers_profiler:
            self._serializers_profiler.StopTiming(container_type)

    return attribute_container