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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 sset_loop(args):
    ''' Loop over all sample sets in a workspace, performing a func '''
    # Ensure that the requested action is a valid fiss_cmd
    fiss_func = __cmd_to_func(args.action)
    if not fiss_func:
        eprint("invalid FISS cmd '" + args.action + "'")
        return 1

    # First get the sample set names
    r = fapi.get_entities(args.project, args.workspace, "sample_set")
    fapi._check_response_code(r, 200)

    sample_sets = [entity['name'] for entity in r.json()]

    args.entity_type = "sample_set"
    for sset in sample_sets:
        print('\n# {0}::{1}/{2} {3}'.format(args.project, args.workspace, sset,
                                            args.action))
        args.entity = sset
        # Note how this code is similar to how args.func is called in
        # main so it may make sense to try to a common method for both
        try:
            result = fiss_func(args)
        except Exception as e:
            status = __pretty_print_fc_exception(e)
            if not args.keep_going:
                return status
        printToCLI(result)

    return 0