# Buggy code
def _ExportEvents(
    self,
    storage_reader,
    event_buffer,
    event_filter=None,
    time_slice=None,
    use_time_slicer=False,
):
    """Exports events using an output module.

    Args:
      storage_reader (StorageReader): storage reader.
      event_buffer (EventBuffer): event buffer.
      event_filter (Optional[FilterObject]): event filter.
      time_slice (Optional[TimeRange]): time range that defines a time slice
          to filter events.
      use_time_slicer (Optional[bool]): True if the 'time slicer' should be
          used. The 'time slicer' will provide a context of events around
          an event of interest.

    Returns:
      collections.Counter: counter that tracks the number of unique events
          read from storage.
    """
    time_slice_buffer = None
    if time_slice:
        if time_slice.event_timestamp is not None:
            time_slice = storage_time_range.TimeRange(
                time_slice.start_timestamp, time_slice.end_timestamp
            )

        if use_time_slicer:
            time_slice_buffer = bufferlib.CircularBuffer(time_slice.duration)

    filter_limit = getattr(event_filter, "limit", None)
    forward_entries = 0

    number_of_filtered_events = 0
    number_of_events_from_time_slice = 0

    for event in storage_reader.GetEvents(time_range=time_slice):
        if event_filter:
            filter_match = event_filter.Match(event)
        else:
            filter_match = None

        # pylint: disable=singleton-comparison
        if filter_match == False:
            if not time_slice_buffer:
                number_of_filtered_events += 1

            elif forward_entries == 0:
                time_slice_buffer.Append(event)
                number_of_filtered_events += 1

            elif forward_entries <= time_slice_buffer.size:
                event_buffer.Append(event)
                self._number_of_consumed_events += 1
                number_of_events_from_time_slice += 1
                forward_entries += 1

            else:
                # We reached the maximum size of the time slice and don't need to
                # include other entries.
                number_of_filtered_events += 1
                forward_entries = 0

        else:
            # pylint: disable=singleton-comparison
            if filter_match == True and time_slice_buffer:
                # Empty the time slice buffer.
                for event_in_buffer in time_slice_buffer.Flush():
                    event_buffer.Append(event_in_buffer)
                    self._number_of_consumed_events += 1
                    number_of_filtered_events += 1
                    number_of_events_from_time_slice += 1

                forward_entries = 1

            event_buffer.Append(event)
            self._number_of_consumed_events += 1

            # pylint: disable=singleton-comparison
            if (
                filter_match == True
                and filter_limit
                and filter_limit == self._number_of_consumed_events
            ):
                break

    events_counter = collections.Counter()
    events_counter["Events filtered"] = number_of_filtered_events
    events_counter["Events from time slice"] = number_of_events_from_time_slice
    events_counter["Events processed"] = self._number_of_consumed_events

    if event_buffer.duplicate_counter:
        events_counter["Duplicate events removed"] = event_buffer.duplicate_counter

    if filter_limit:
        events_counter["Limited By"] = filter_limit

    return events_counter


# Traceback (KeyError)
[ERROR] (nsrlsvr   ) PID:XXXXX <analysis_process> <dfvfs.path.os_path_spec.OSPathSpec object at 0xXXXXXXXXXXXX>
Traceback (most recent call last):
File "/usr/lib/python2.7/dist-packages/plaso/multi_processing/analysis_process.py", line 138, in _Main
self._analysis_mediator.ProduceAnalysisReport(self._analysis_plugin)
File "/usr/lib/python2.7/dist-packages/plaso/analysis/mediator.py", line 95, in ProduceAnalysisReport
analysis_report = plugin.CompileReport(self)
File "/usr/lib/python2.7/dist-packages/plaso/analysis/interface.py", line 280, in CompileReport
hash_analysis)
File "/usr/lib/python2.7/dist-packages/plaso/analysis/interface.py", line 187, in _HandleHashAnalysis
event_uuids = self._event_uuids_by_pathspec.pop(pathspec)
KeyError: <dfvfs.path.os_path_spec.OSPathSpec object at 0xXXXXXXXXXXXX>

# Fixed code
def _ExportEvents(
    self,
    storage_reader,
    event_buffer,
    event_filter=None,
    time_slice=None,
    use_time_slicer=False,
):
    """Exports events using an output module.

    Args:
      storage_reader (StorageReader): storage reader.
      event_buffer (EventBuffer): event buffer.
      event_filter (Optional[FilterObject]): event filter.
      time_slice (Optional[TimeRange]): time range that defines a time slice
          to filter events.
      use_time_slicer (Optional[bool]): True if the 'time slicer' should be
          used. The 'time slicer' will provide a context of events around
          an event of interest.

    Returns:
      collections.Counter: counter that tracks the number of unique events
          read from storage.
    """
    self._status = definitions.PROCESSING_STATUS_EXPORTING

    time_slice_buffer = None
    if time_slice:
        if time_slice.event_timestamp is not None:
            time_slice = storage_time_range.TimeRange(
                time_slice.start_timestamp, time_slice.end_timestamp
            )

        if use_time_slicer:
            time_slice_buffer = bufferlib.CircularBuffer(time_slice.duration)

    filter_limit = getattr(event_filter, "limit", None)
    forward_entries = 0

    number_of_filtered_events = 0
    number_of_events_from_time_slice = 0

    for event in storage_reader.GetEvents(time_range=time_slice):
        if event_filter:
            filter_match = event_filter.Match(event)
        else:
            filter_match = None

        # pylint: disable=singleton-comparison
        if filter_match == False:
            if not time_slice_buffer:
                number_of_filtered_events += 1

            elif forward_entries == 0:
                time_slice_buffer.Append(event)
                number_of_filtered_events += 1

            elif forward_entries <= time_slice_buffer.size:
                event_buffer.Append(event)
                self._number_of_consumed_events += 1
                number_of_events_from_time_slice += 1
                forward_entries += 1

            else:
                # We reached the maximum size of the time slice and don't need to
                # include other entries.
                number_of_filtered_events += 1
                forward_entries = 0

        else:
            # pylint: disable=singleton-comparison
            if filter_match == True and time_slice_buffer:
                # Empty the time slice buffer.
                for event_in_buffer in time_slice_buffer.Flush():
                    event_buffer.Append(event_in_buffer)
                    self._number_of_consumed_events += 1
                    number_of_filtered_events += 1
                    number_of_events_from_time_slice += 1

                forward_entries = 1

            event_buffer.Append(event)
            self._number_of_consumed_events += 1

            # pylint: disable=singleton-comparison
            if (
                filter_match == True
                and filter_limit
                and filter_limit == self._number_of_consumed_events
            ):
                break

    events_counter = collections.Counter()
    events_counter["Events filtered"] = number_of_filtered_events
    events_counter["Events from time slice"] = number_of_events_from_time_slice
    events_counter["Events processed"] = self._number_of_consumed_events

    if event_buffer.duplicate_counter:
        events_counter["Duplicate events removed"] = event_buffer.duplicate_counter

    if filter_limit:
        events_counter["Limited By"] = filter_limit

    return events_counter