docs: def primary_container_name(names, default=None, strip_trailing_slash=True):
      """
      From the list of names, finds the primary name of the container. Returns the defined default value (e.g. the
      container id or ``None``) in case it cannot find any.
  
      :param names: List with name and aliases of the container.
      :type names: list[unicode | str]
      :param default: Default value.
      :param strip_trailing_slash: As read directly from the Docker service, every container name includes a trailing
       slash. Set this to ``False`` if it is already removed.
      :type strip_trailing_slash: bool
      :return: Primary name of the container.
      :rtype: unicode | str
      """
      if strip_trailing_slash:
          ex_names = [name[1:] for name in names if name.find('/', 2) == -1]
      else:
          ex_names = [name for name in names if name.find('/', 2) == -1]
      if ex_names:
          return ex_names[0]
      return default