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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 parse_cat_ini_opt(cat_str):
 """ Parse a cat str from the ini file into a list of sets """

    if cat_str == "":
        return []

    cat_groups = cat_str.split(',')
    cat_sets = []
    for group in cat_groups:
        group = group.strip()
        cat_sets += [set(c for c in group)]
    return cat_sets