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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def species_list(what_list):
    '''
    provide default lists of elements to plot.

    what_list : string
        String name of species lists provided.

        If what_list is "CNONe", then C, N, O and some other light
        elements.

        If what_list is "s-process", then s-process indicators.

    '''
    if what_list is "CNONe":
        list_to_print = ['H-1','He-4','C-12','N-14','O-16','Ne-20']
    elif what_list is "sprocess":
        list_to_print = ['Fe-56','Ge-70','Zn-70','Se-76','Kr-80','Kr-82','Kr-86','Sr-88','Ba-138','Pb-208']
    elif what_list is "burn_stages":
        list_to_print = ['H-1','He-4','C-12','O-16','Ne-20','Si-28']
    elif what_list is "list_marco_1":
        list_to_print = ['C-12','O-16','Ne-20','Ne-22','Na-23','Fe-54','Fe-56','Zn-70','Ge-70','Se-76','Kr-80','Kr-82','Sr-88','Y-89','Zr-96','Te-124','Xe-130','Xe-134','Ba-138']

    return list_to_print