new_contents: """
  A helper module for testing, introducing some helper functions. Inspired by
  the jedi helper module for their testing package
  """
  import os
  from os.path import abspath, dirname
  import functools
  
  test_dir = dirname(abspath(__file__))
  
  
  def cwd_at(path):
      """
      Decorator to run function at `path`.
  
      :type path: str
      :arg path: relative path from repository root (e.g., ``'jedi'``).
      """
      def decorator(func):
          @functools.wraps(func)
          def wrapper(*args, **kwds):
              try:
                  oldcwd = os.getcwd()
                  repo_root = os.path.dirname(test_dir)
                  os.chdir(os.path.join(repo_root, path))
                  return func(*args, **kwds)
              finally:
                  os.chdir(oldcwd)
          return wrapper
      return decorator
subject: Add a helpers module to the testing package