Buggy python submission (verdict: Runtime Error):
from scipy.sparse.csgraph import floyd_warshall

n,m=map(int,input().split())
l=[list(map(int,input().split())) for i in range(m)]

cnt=0
for i in range(m):
  ll=deepcopy(l)
  del ll[i]

  d=[[float('inf')]*n for i in range(n)]
  for i in range(n):
    d[i][i]=0

  for a,b in ll:
    a-=1
    b-=1
    d[a][b]=1
    d[b][a]=1

  s=floyd_warshall(d)
  for i in s:
    if float('inf') in i:
      cnt+=1
      break

print(cnt)

Fixed submission:
from collections import deque

n,m=map(int,input().split())
l=[list(map(int,input().split())) for i in range(m)]

def make_dict(x,y):
    for i in ll:
        if i[x] in d.keys():
            d[i[x]]+=[i[y]]
        else:
            d[i[x]]=[i[y]]

cnt=0
for i in range(m):
    ll=l[:i]+l[i+1:]
#    print(ll)
    d={}
    make_dict(0,1)
    make_dict(1,0)
#    print(d)
    k_l=list(d.keys())
    v_l=list(d.values())
#    print(k_l)

    x=0
    sk=k_l[x]
    dq=deque()
    dq.append(sk)
#    while dq:
#    print(dq)
#    x=0
    seen=[]
    while dq:
#    while n<10:
        k=dq.pop()
        k_ll=d[k]
        seen.append(k)
#        print(k_ll)
        for i in k_ll:
            if i not in seen:
                dq.append(i)
#        d=d.pop(sk)
#        print(dq)
        x+=1
#    print(set(seen),len(set(seen)))
    if len(set(seen))!=n:
        cnt+=1
print(cnt)

Buggy python submission (verdict: Runtime Error):
from scipy.sparse.csgraph import floyd_warshall

n,m=map(int,input().split())
l=[list(map(int,input().split())) for i in range(m)]

ans=0
for i in range(m):
    ll=l[:i]+l[i+1:]

    d=[[float('inf')]*n for i in range(n)]
    for i in range(n):
        d[i][i]=0

    for j in ll:
        d[j[0]-1][j[1]-1]=1
        d[j[1]-1][j[0]-1]=1

    d=floyd_warshall(d)

    if float('inf') in d:
        ans+=1

print(ans)

Fixed submission:
from collections import deque

n,m=map(int,input().split())
l=[list(map(int,input().split())) for i in range(m)]

def make_dict(x,y):
    for i in ll:
        if i[x] in d.keys():
            d[i[x]]+=[i[y]]
        else:
            d[i[x]]=[i[y]]

cnt=0
for i in range(m):
    ll=l[:i]+l[i+1:]
#    print(ll)
    d={}
    make_dict(0,1)
    make_dict(1,0)
#    print(d)
    k_l=list(d.keys())
    v_l=list(d.values())
#    print(k_l)

    x=0
    sk=k_l[x]
    dq=deque()
    dq.append(sk)
#    while dq:
#    print(dq)
#    x=0
    seen=[]
    while dq:
#    while n<10:
        k=dq.pop()
        k_ll=d[k]
        seen.append(k)
#        print(k_ll)
        for i in k_ll:
            if i not in seen:
                dq.append(i)
#        d=d.pop(sk)
#        print(dq)
        x+=1
#    print(set(seen),len(set(seen)))
    if len(set(seen))!=n:
        cnt+=1
print(cnt)

Buggy python submission (verdict: Runtime Error):
from scipy.sparse.csgraph import floyd_warshall

n,m=map(int,input().split())
l=[list(map(int,input().split())) for i in range(m)]

ans=0
for i in range(m):
    ll=l[:i]+l[i+1:]

    d=[[float('inf')]*n for i in range(n)]
    for i in range(n):
        d[i][i]=0

    for j in ll:
        d[j[0]-1][j[1]-1]=1
        d[j[1]-1][j[0]-1]=1

    d=floyd_warshall(d)

    if float('inf') in d:
        ans+=1

print(ans)

Fixed submission:
from collections import deque

n,m=map(int,input().split())
l=[list(map(int,input().split())) for i in range(m)]

def make_dict(x,y):
    for i in ll:
        if i[x] in d.keys():
            d[i[x]]+=[i[y]]
        else:
            d[i[x]]=[i[y]]

cnt=0
for i in range(m):
    ll=l[:i]+l[i+1:]
#    print(ll)
    d={}
    make_dict(0,1)
    make_dict(1,0)
#    print(d)
    k_l=list(d.keys())
    v_l=list(d.values())
#    print(k_l)

    x=0
    sk=k_l[x]
    dq=deque()
    dq.append(sk)
#    while dq:
#    print(dq)
#    x=0
    seen=[]
    while dq:
#    while n<10:
        k=dq.pop()
        k_ll=d[k]
        seen.append(k)
#        print(k_ll)
        for i in k_ll:
            if i not in seen:
                dq.append(i)
#        d=d.pop(sk)
#        print(dq)
        x+=1
#    print(set(seen),len(set(seen)))
    if len(set(seen))!=n:
        cnt+=1
print(cnt)