class_docstr: Base support interface for NiftyReg commands.
class_docstr_tok: ["Base","support","interface","for","NiftyReg","commands","."]
code: def exists(self):
      return self.version is not None
  
imports: import os
  from packaging.version import Version
  from ...None import logging
  from ..base import CommandLine, CommandLineInputSpec, traits, Undefined, PackageInfo
  from ...utils.filemanip import split_filename
label_desc: Use image node_id 6 for calling the NiftyRegCommand obj's underlying member method code with example usage: obj.exists() and returns: unknown