code: def fix_subparsers(subparsers):
      
      from dvc.utils.compat import is_py3
  
      if is_py3:  # pragma: no cover
          subparsers.required = True
          subparsers.dest = "cmd"
docs: Workaround for bug in Python 3. See more info at:
          https://bugs.python.org/issue16308
          https://github.com/iterative/dvc/issues/769
  
          Args:
              subparsers: subparsers to fix.