Sorting Elements of an Array by Frequency

def myfun(a):
    return a[0],-a[1]
t=int(input())
while t>0:
    t-=1
    n=int(input())
    arr=[int(i) for i in input().split()]
    dict={}
    for i in arr:
        if i in dict.keys():
            dict[i]+=1
        else:
            dict[i]=1
    arr=[[v,k] for k,v in dict.items()]
    arr.sort(reverse=True,key=myfun)
    ans=[]
    for i in arr:
        a,b=i[0],i[1]
        for k in range(a):
            print(b,end=" ")
    print()