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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _ExtractContentFromDataStream( self, mediator, file_entry, data_stream_name):
 """Extracts content from a data stream. Args: mediator (ParserMediator):
 mediates the interactions between parsers and other components, such as storage and abort signals. file_entry (dfvfs.FileEntry):
 file entry to extract its content. data_stream_name (str):
 name of the data stream whose content is to be extracted. """

    self.processing_status = definitions.STATUS_INDICATOR_EXTRACTING

    if self._processing_profiler:
      self._processing_profiler.StartTiming('extracting')

    self._event_extractor.ParseDataStream(
        mediator, file_entry, data_stream_name)

    if self._processing_profiler:
      self._processing_profiler.StopTiming('extracting')

    self.processing_status = definitions.STATUS_INDICATOR_RUNNING

    self.last_activity_timestamp = time.time()