Help

Hi guys I stuck here

from collections import Counter
r=list(rings)
count=0

while r:
    d=Counter(x for sublist in r for x in sublist)
    a=d.most_common()
    d=a[0][0]
    for i in r[:]:
        if d in i:
            r.remove(i)
    count+=1
return count

can't pass extra test 8 Any help???

I also try another solution but same thing

    from collections import Counter
    r = list (({3,4},{5,6},{2,7},{1,5},{2,6},{8,4},{1,7},{4,5},{9,5},{2,3},{8,2},{2,4},{9,6},{5,7},{3,6},{1,3},))
    count=0
    count2=0
    c=list(r)
    while r:
       d=Counter(x for sublist in r for x in sublist)
       a=d.most_common()
       d=a[0][0]
       for i in r[:]:
        if d in i:
            r.remove(i)
       count+=1
    while c:
       d=Counter(x for sublist in c for x in sublist)
       a=d.most_common()
       d=a[0][0]
       if a[0][1] ==a [1][1]:
        d=a[1][0]
       for i in c[:]:
        if d in i:
            c.remove(i)
       count2+=1


    if count > count2:
       print(count)
    else: 
       print(count2)