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#include <bits/stdc++.h>
#define e using u=ostream;template<class a,class b>u&operator<<(u&o,pair<a,b>&x)
using namespace std;e;u&operator<<(u&o,string&s){return o<<s.c_str();}template<
class t>auto operator<<(u&o,t&x)->decltype(x.end(),o){o<<'{';int i=2;for(auto y:
x)o<<", "+i<<y,i=0;return o<<'}';}e{return o<<'('<<x.first<<", "<<x.second<<')';}
#ifdef DEBUG
#define LOG(x...)cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...)<<'\n';}(x)
#else
#define LOG(...)
#endif
#define ff first
#define ss second
#define ll long long
const ll maxn = 5000000;

const ll mod = 1000000007;
vector <ll> fact(maxn);


ll fastpow(ll a, ll b) {
	ll res = 1;
	a %= mod;
	while (b) {
		if (b & 1) res = res * a % mod;
		a *= a;
		a %= mod;
		b >>= 1;
	}
	return res;
}

void makefact() {
	fact[0] = 1;
    for (ll i = 1; i < maxn; i++) {
		fact[i] = fact[i-1] * i;
		fact[i] %= mod;
    }
}

ll count(ll n) {
	ll numerator = 1LL * n % mod * (2LL*n - 1) % mod * fact[4LL*n - 2] % mod;
	ll denom = fastpow(2, 2LL*n - 1);
	ll odwr = fastpow(denom, mod - 2);
	return numerator * odwr % mod;
}

ll tylko1(ll n) {
	ll numerator = n * fact[4LL*n] % mod;
	ll denom = (4*n-1) * fastpow(2, 2*n) % mod;
	ll odwr = fastpow(denom, mod - 2);
	return numerator * odwr % mod;
}

map <vector <int>, int> table2 = {
    {{0, 0, 0, 0}, 540},
    {{0, 0, 1, 0}, 54},
    {{1, 0, 0, 0}, 54},
    {{1, 0, 1, 0}, 24},
    {{1, 0, 1, 1}, 114},
    {{1, 1, 1, 0}, 114},
    {{1, 1, 1, 1}, 720},
    {{1, 1, 2, 1}, 114},
    {{2, 1, 1, 1}, 114},
    {{2, 1, 2, 1}, 24},
    {{2, 1, 2, 2}, 54},
    {{2, 2, 2, 1}, 54},
    {{2, 2, 2, 2}, 540},
};

map <vector <int>, int> table3 = {
    {{0, 0, 0, 0, 0, 0}, 1701000},
    {{0, 0, 0, 0, 1, 0}, 63000},
    {{0, 0, 1, 0, 0, 0}, 63000},
    {{0, 0, 1, 0, 1, 0}, 8640},
    {{0, 0, 1, 1, 1, 0}, 108360},

    {{1, 0, 0, 0, 0, 0}, 63000},
    {{1, 0, 0, 0, 1, 0}, 8640},
    {{1, 0, 0, 0, 1, 1}, 108360},
    {{1, 0, 1, 0, 0, 0}, 8640},
    {{1, 0, 1, 0, 1, 0}, 1080},
    {{1, 0, 1, 0, 1, 1}, 11160},
    {{1, 0, 1, 1, 1, 0}, 11160},
    {{1, 0, 1, 1, 1, 1}, 148680},

    {{1, 1, 1, 0, 0, 0}, 108360},
    {{1, 1, 1, 0, 1, 0}, 11160},
    {{1, 1, 1, 0, 1, 1}, 148680},
    {{1, 1, 1, 1, 1, 0}, 148680},
    {{1, 1, 1, 1, 1, 1}, 2041200},
    {{1, 1, 1, 1, 2, 1}, 148680},

    {{1, 1, 2, 1, 1, 1}, 148680},
    {{1, 1, 2, 1, 2, 1}, 11160},
    {{1, 1, 2, 2, 2, 1}, 108360},

    {{2, 1, 1, 1, 1, 1}, 148680},
    {{2, 1, 1, 1, 2, 1}, 11160},
    {{2, 1, 1, 1, 2, 2}, 108360},
    {{2, 1, 2, 1, 1, 1}, 11160},
    {{2, 1, 2, 1, 2, 1}, 1080},
    {{2, 1, 2, 1, 2, 2}, 8640},
    {{2, 1, 2, 2, 2, 1}, 8640},
    {{2, 1, 2, 2, 2, 2}, 63000},

    {{2, 2, 2, 1, 1, 1}, 108360},
    {{2, 2, 2, 1, 2, 1}, 8640},
    {{2, 2, 2, 1, 2, 2}, 63000},
    {{2, 2, 2, 2, 2, 1}, 63000},
    {{2, 2, 2, 2, 2, 2}, 1701000},
};



int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int t;
	makefact();
	cin >> t;
	while (t--) {
		int n;
		cin >> n;
		vector <int> cnt(3);
		vector <int> v(2*n);
		for (int i = 0; i < 2*n; i++) {
			cin >> v[i];
			cnt[v[i]]++;
		}
		if (cnt[0] && cnt[2]) {
			cout << "0\n";
			continue;
		}
		if (cnt[1] == 0) {
			cout << count(n) << "\n";
			continue;
		}
		if (n == 1) {
			if (cnt[0] == 2 || cnt[2] == 2) {
				cout << "1\n";
				continue;
			}
			if (cnt[1] == 2) {
				cout << "4\n";
				continue;
			}
			cout << "0\n";
			continue;
		}
		if (n == 2) {
			if (table2.find(v) == table2.end()) {
				cout << "0\n";
			}
			else {
				cout << table2[v] << "\n";
			}
			continue;
		}
		if (n == 3) {
			if (table3.find(v) == table3.end()) {
				cout << "0\n";
			}
			else {
				cout << table3[v] << "\n";
			}
			continue;
		}
		if (cnt[0] == 0 && cnt[2] == 0) {
			cout << tylko1(n) << "\n";
			continue;
		}
		cout << "0\n";
	}
}