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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 ExamineEvent(self, mediator, event):
 """Analyzes an event and creates extracts hashes as required. Args: mediator (AnalysisMediator):
 mediates interactions between analysis plugins and other components, such as storage and dfvfs. event (EventObject):
 event to examine. """

    pathspec = getattr(event, 'pathspec', None)
    if pathspec is None:
      return
    if self._paths_with_hashes.get(pathspec, None):
      # We've already processed an event with this pathspec and extracted the
      # hashes from it.
      return
    hash_attributes = {}
    for attribute_name, attribute_value in event.GetAttributes():
      if attribute_name.endswith('_hash'):
        hash_attributes[attribute_name] = attribute_value
    self._paths_with_hashes[pathspec] = hash_attributes