def retrieve_stns(stns_dict, *stn):
    """
    function to retrieve Station objects for requested stations
    :param stns_dict: dictionary of Station objects from adj/apu/xyz read
    :param stn: name of station to be retrieved
    :return: list of Station objects
    """

    stns = []

    for s in stn:
        try:
            stns.append(stns_dict[s])
        except KeyError:
            raise ValueError(f'{s} not found in .apu file')

    return stns