code: def ram_drive_path(path=None):
      """
      :param path: path relative to the ram drive.
      :return: absolute path inside the ram drive directory or None if no ram drive was provided by environment.
      """
      if "YA_TEST_RAM_DRIVE_PATH" in os.environ:
          return _join_path(os.environ["YA_TEST_RAM_DRIVE_PATH"], path)
      elif get_param("ram_drive_path"):
          return _join_path(get_param("ram_drive_path"), path)
  
imports: import errno
  import functools
  import json
  import os
  import sys
  import threading
  import six
label_desc: Use image node_id 20 for calling a global function with example usage: ram_drive_path(path) and returns: _join_path, _join_path