code: def _find_source_root(source_abs_path):
      # Note that READTHEDOCS* environment variable cannot be used, because they
      # are not set under docker environment.
      global _source_root
      if _source_root is None:
          dir = os.path.dirname(source_abs_path)
          while True:
              if _is_egg_directory(dir) or _is_git_root(dir):
                  # Reached the root directory
                  _source_root = dir
                  break
  
              dir_ = os.path.dirname(dir)
              if len(dir_) == len(dir):
                  raise RuntimeError(
                      "Couldn't parse root directory from "
                      "source file: {}".format(source_abs_path)
                  )
              dir = dir_
      return _source_root
  
file_path: chainercv/docs/source/conf.py
imports: import inspect
  import os
  import pkg_resources
  import sys
label_desc: Use image node_id 4 for calling a global function with example usage: _find_source_root(source_abs_path) and returns: _source_root