Three Counters

three-count.py

counters = {key:collections.Counter() for key in ['child','mother','father']}
with open("day2/names.csv") as f:
    rdr = csv.DictReader(f)
    for r in rdr:
        for key in counters:
            l = r[key].split()
            if len(l)>0:
                counters[key][l[0]] += 1
                
commonize = lambda ctr,N: {t[0] for t in ctr.most_common(N)}

common = {key:commonize(ctr,10) for key,ctr in counters.items()}
common