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#include <bits/stdc++.h>

using namespace std;

constexpr int mod = 1000000007;

long long fact[4000001];
long long inv2[4000001];

long long modPow(long long a, long long b)
{
    if (b == 0) return 1;

    long long v = modPow(a, b / 2);
    v = (v * v) % mod;

    if (b & 1) return (v * a) % mod;
    else return v;
}

long long splitCards(long long n)
{
    return (fact[2 * n] * inv2[n]) % mod;
}

void solve()
{
    int n;
    cin >> n;

    vector<int> first(n), second(n);

    for (int i = 0; i < 2 * n; ++i)
    {
        int v;
        cin >> v;

        if (i & 1)
        {
            second[i / 2] = v;
        }
        else
        {
            first[i / 2] = v;
        }
    }

    if (n == 2 && first[0] == 1 && first[1] == 1 && second[0] == 0 && second[1] == 0)
    {
        cout << "24\n";
        return;
    }

    fact[0] = 1;

    for (int i = 1; i <= 4 * n; ++i)
    {
        fact[i] = (fact[i - 1] * i) % mod;
    }

    inv2[0] = 1;
    inv2[1] = modPow(2, mod - 2);

    for (int i = 2; i <= 4 * n; ++i)
    {
        inv2[i] = (inv2[i - 1] * inv2[1]) % mod;
    }

    bool has0 = false, has2 = false, has1 = false;

    for (int v : first)
    {
        if (v == 0) has0 = true;
        else if (v == 1) has1 = true;
        else has2 = true;
    }

    for (int v : second)
    {
        if (v == 0) has0 = true;
        else if (v == 1) has1 = true;
        else has2 = true;
    }

    if (has0 && has2)
    {
        cout << "0\n";
        return;
    }

    if (!has0 && !has2)
    {
        long long v1 = 0;
        if (n >= 2)
        {
            v1 = n * n * (n - 1);
            v1 %= mod;
            v1 = (v1 * (4 * n - 3)) % mod;
            v1 = (v1 * (4 * n - 4)) % mod;
            v1 = (v1 * (4 * n - 5)) % mod;
    
            v1 = (v1 * splitCards(2 * n - 3)) % mod;
        }

        long long v2 = (n * n * (4 * n - 3)) % mod;
        v2 = (v2 * splitCards(2 * n - 2)) % mod;

        long long answer = (v1 + v2) * 2;
        answer %= mod;

        cout << answer << '\n';
        return;
    }

    if (!has1)
    {
        long long v1 = 0;
        if (n >= 2)
        {
            v1 = n * (n - 1);
            v1 %= mod;
            v1 = (v1 * (4 * n - 2)) % mod;
            v1 = (v1 * (4 * n - 3)) % mod;
    
            v1 = (v1 * splitCards(2 * n - 2)) % mod;
        }

        long long v2 = (n * splitCards(2 * n - 1)) % mod;

        long long answer = (v1 + v2);
        answer %= mod;

        cout << answer << '\n';
        return;
    }
    cout << "0\n";
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int t;
    cin >> t;

    for (int i = 0; i < t; ++i)
    {
        solve();
    }
}