docs: def tz_file(name):
      """
      Open a timezone file from the zoneinfo subdir for reading.
  
      :param name: The name of the timezone.
      :type name: str
  
      :rtype: file
      """
      try:
          filepath = tz_path(name)
  
          return open(filepath, 'rb')
      except TimezoneNotFound:
          # http://bugs.launchpad.net/bugs/383171 - we avoid using this
          # unless absolutely necessary to help when a broken version of
          # pkg_resources is installed.
          try:
              from pkg_resources import resource_stream
          except ImportError:
              resource_stream = None
  
          if resource_stream is not None:
              try:
                  return resource_stream(__name__, 'zoneinfo/' + name)
              except FileNotFoundError:
                  return tz_path(name)
  
          raise