class_docstr: For internal use
      
class_docstr_tok: ["For","internal","use"]
code: def __cmp__(self, other):
      if other is self:
          return 0
      raise TypeError("UNKNOWN version is not comparable")
  
imports: import os.path
  import re
  import sys
  from itertools import chain
  from os import linesep
  from looseversion import LooseVersion
  from datalad.config import get_git_version
  from datalad.log import lgr
  from .exceptions import CapturedException, CommandError
  from datalad.cmd import GitWitlessRunner, StdOutErrCapture, WitlessRunner
  from datalad.support.exceptions import MissingExternalDependency, OutdatedExternalDependency
label_desc: Use image node_id 2 for calling the UnknownVersion obj's underlying member method code with example usage: obj.__cmp__(other) and returns: int