class_docstr: Representation of a Git repository
  
      
docstr: Returns whether the underlying repository appears to be still valid
  
  This method can be used as an instance method or a class method.
docstr_tok: ["Returns","whether","the","underlying","repository","appears","to","be","still","valid","This","method","can","be","used","as","an","instance","method","or","a","class","method","."]
code: def is_valid(self_or_path):
      """Returns whether the underlying repository appears to be still valid
  
      This method can be used as an instance method or a class method.
      """
      # preserving notes from the original implementations in GitRepo
      #
      # Note, that this almost identical to the classmethod is_valid_repo().
      # However, if we are testing an existing instance, we can save Path object
      # creations. Since this testing is done a lot, this is relevant. Creation
      # of the Path objects in is_valid_repo() takes nearly half the time of the
      # entire function.
  
      # Also note, that this method is bound to an instance but still
      # class-dependent, meaning that a subclass cannot simply overwrite it.
      # This is particularly important for the call from within __init__(),
      # which in turn is called by the subclasses' __init__. Using an overwrite
      # would lead to the wrong thing being called.
      if not isinstance(self_or_path, GitRepo):
          # called like a classmethod, perform test without requiring
          # a repo instance
          if not isinstance(self_or_path, Path):
              self_or_path = Path(self_or_path)
          dot_git_path = self_or_path / ".git"
          return (
              dot_git_path.exists()
              and (
                  not dot_git_path.is_dir()
                  or (dot_git_path / "HEAD").exists()
              )
          ) or (self_or_path / "HEAD").exists()
      else:
          # called as a method of a repo instance
          return self_or_path.dot_git.exists() and (
              not self_or_path.dot_git.is_dir()
              or self_or_path._valid_git_test_path.exists()
          )
  
imports: import logging
  import re
  import threading
  import time
  from contextlib import contextmanager
  from locale import getpreferredencoding
  from os import environ
  from os.path import lexists
  from typing import Optional
  from weakref import finalize, WeakValueDictionary
  from datalad.cmd import GitWitlessRunner, StdOutErrCapture
  from datalad.config import ConfigManager
  from datalad.dataset.repo import PathBasedFlyweight, RepoInterface, path_based_str_repr
  from datalad.runner.nonasyncrunner import STDERR_FILENO, STDOUT_FILENO
  from datalad.runner.protocol import GeneratorMixIn
  from datalad.runner.utils import AssemblingDecoderMixIn, LineSplitter
  from datalad.support.exceptions import CommandError, GitIgnoreError, InvalidGitRepositoryError, PathKnownToRepositoryError
  from datalad.utils import ensure_list, lock_if_required, Path
label_desc: Use image node_id 7 for calling the GitRepo obj's underlying member method code with example usage: obj.is_valid(_or_path) and returns: unknown, unknown