// UUID: 62c3ccc5-90ca-4aa8-9202-2cc869f3b475
    #include <bits/stdc++.h>
    
    using namespace std;
    
    #define ll long long
    #define fs first
    #define sc second
    #define pb push_back
    #define pll pair<ll, ll>
    #define vll vector<ll>
    #define v2ll vector<vll>
    #define pqll priority_queue<ll>

    const ll mod = 1e9+7;
    const ll inf = LONG_LONG_MAX;

    ll n, k;
    vector<bool> vis, c;
    v2ll g;
    bool possible;

    void dfs(ll p) {
        vis[p] = 1;
        for (ll i : g[p]) {
            if (!vis[i]) {
                c[i] = 1-c[p];
                dfs(i);
            } else if (c[p] == c[i])
                possible = false;
        }
    }

    void solve()
    {
        cin >> n >> k;
        g.assign(n+1, vll(0, 0)); vis.assign(n+1, 0); c.assign(n+1, 0);
        possible = true;
        for (ll i = 0; i < k; i++) {
            ll a, b;
            cin >> a >> b;
            g[a-1].pb(b);
            g[b].pb(a-1);
        }
        ll ans = 0;
        dfs(0);
        if (possible) ans++;
        for (ll i = 1; i <= n; i++) {
            if (!possible) break;
            if (!vis[i]) {
                dfs(i);
                if (possible) {
                    ans *= 2;
                }
                else ans = 0;
                ans %= mod;
            }
        }
        cout << ans << '\n';
    }
    
    signed main()
    {
        ios_base::sync_with_stdio(false);
        cin.tie(NULL); cout.tie(NULL);
        ll t = 1;
        cin >> t;
        while(t--)
        {
            solve();
        }
        return 0;
    }