code: def main(self, args):
      LabConfig(
          settings_file=args.settings_file
      ).read().unset_default_viewers(args.doctype).write()
      return 0
  
imports: import sys
  from argparse import ArgumentParser
  from pathlib import Path
  import jupyter_core.paths
  from .labconfig import LabConfig
label_desc: Use image node_id 2 for calling the UnsetDefaultViewer obj's underlying member method code with example usage: obj.main(args) and returns: int