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

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