Many Cycles

def deletethosefucks(j):
	if j in graph.keys() and (len(graph[j]) <= 1 or len(graph[j]) == 2 and graph[j].__contains__(j)):
		nodestochecknext = graph[j]
		del graph[j]
		for node in nodestochecknext:
			if node in graph.keys():
				graph[node].remove(j)
#				deletethosefucks(node)
		for node in nodestochecknext:
#			if node in graph.keys():
#				graph[node].remove(j)
			deletethosefucks(node)

cases = int(input())

for i in range(cases):
	nodes, edges = list(map(int, input().split()))	 
	graph = {}
	for j in range(nodes):
		graph[j + 1] = []	
	for _ in range(edges):
		a, b = list(map(int, input().split()))
		graph[a].append(b)
		if b != a:
			graph[b].append(a)
	for j in graph.keys():
		deletethosefucks(j)
	for j in graph.keys():
		if len(graph[j]) > 2:
			print("YES")
			break
	else:
		print("NO")
	

#	for arr in graph.values():
#		print(arr)
#		if (len(arr) > 2):
#			a += 1
#	if a > 1:
#		print("YES")
#	else:
#		print("NO")

Test 1

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 26, in <module>
    for j...

Test 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 26, in <module>
    for j...