#include <iostream>
#include <algorithm>
#include <string>
#include <map>
#include <assert.h>
using namespace std;
 
 
 
long long readInt(long long l,long long r,char endd){
	long long x=0;
	int cnt=0;
	int fi=-1;
	bool is_neg=false;
	while(true){
		char g=getchar();
		if(g=='-'){
			assert(fi==-1);
			is_neg=true;
			continue;
		}
		if('0'<=g && g<='9'){
			x*=10;
			x+=g-'0';
			if(cnt==0){
				fi=g-'0';
			}
			cnt++;
			assert(fi!=0 || cnt==1);
			assert(fi!=0 || is_neg==false);
			
			assert(!(cnt>19 || ( cnt==19 && fi>1) ));
		} else if(g==endd){
			assert(cnt>0);
			if(is_neg){
				x= -x;
			}
			if(!(l<=x && x<=r)){
				cerr<<l<<" "<<r<<" "<<x<<endl;
			}
			assert(l<=x && x<=r);
			return x;
		} else {
			assert(false);
		}
	}
}
string readString(int l,int r,char endd){
	string ret="";
	int cnt=0;
	while(true){
		char g=getchar();
		assert(g!=-1);
		if(g==endd){
			break;
		}
		cnt++;
		ret+=g;
	}
	assert(l<=cnt && cnt<=r);
	return ret;
}
long long readIntSp(long long l,long long r){
	return readInt(l,r,' ');
}
long long readIntLn(long long l,long long r){
	return readInt(l,r,'\n');
}
string readStringLn(int l,int r){
	return readString(l,r,'\n');
}
string readStringSp(int l,int r){
	return readString(l,r,' ');
}

int T;
int n;
int sm_n=0;
int arr[100100];
long long mod =1000000007;
long long fact(int n){
	long long ret=1;
	for(int i=1;i<=n;i+=2){
		ret *= i;
		ret %= mod;
	}
	return ret;
}

map<int,int> rep;
map<int,int>::reverse_iterator ii;
int main(){
	//freopen("00.txt","r",stdin);
	//freopen("00o.txt","w",stdout);
	T=readIntLn(1,1000);
	while(T--){
		n=readIntLn(1,100000);
		assert(n % 2 ==0);
		sm_n += n;
		rep.clear();
		assert(sm_n<=1000000);
		for(int i=1;i<=n;i++){
			if(i==n){
				arr[i]=readIntLn(1,1000000);
			} else {
				arr[i]=readIntSp(1,1000000);
			}
			rep[arr[i]]++;
		}
		long long sol=1;
		bool carry=false;
		for(ii=rep.rbegin();ii!=rep.rend();ii++){
			int cur=ii->second;
			if (carry ){
				sol *= cur;
				cur--;
				sol %= mod;
				carry=false;
			}
			if(cur % 2) carry =true;
			sol *= fact(cur);
			sol %= mod;
		}
		cout<<sol<<endl;
	}
	assert(getchar()==-1);
}