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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 _FormatInode(self, event):
 """Formats the inode. Args: event (EventObject):
 event. Returns: str: inode field. """

    inode = event.inode
    if inode is None:
      if hasattr(event, 'pathspec') and hasattr(event.pathspec, 'image_inode'):
        inode = event.pathspec.image_inode
    if inode is None:
      inode = '-'

    return inode