#include <bits/stdc++.h>
#define show(x) std::cerr << #x << " = " << x << std::endl
using ll = long long;
constexpr ll MOD = 1000000007LL;
template <ll mod = MOD>
class ModCombination
{
public:
    ModCombination(const std::size_t n) : fact(n + 1, 1), inv(n + 1, 1), inv_fact(n + 1, 1)
    {
        for (ll i = 2; i <= (ll)n; i++) { fact[i] = (fact[i - 1] * i) % mod, inv[i] = ((mod - (mod / i)) * inv[mod % i]) % mod, inv_fact[i] = (inv_fact[i - 1] * inv[i]) % mod; }
    }
    ll factorial(const std::size_t n) const { return fact[n]; }
    ll inverse(const std::size_t n) const { return inv[n]; }
    ll inverseFactorial(const std::size_t n) const { return inv_fact[n]; }
    ll permutation(const std::size_t n, const std::size_t k) const { return (fact[n] * inv_fact[n - k]) % mod; }
    ll combination(const std::size_t n, const std::size_t k) const { return (((fact[n] * inv_fact[k]) % mod) * inv_fact[n - k]) % mod; }

private:
    std::vector<ll> fact, inv, inv_fact;
};
int main()
{
    int N;
    std::cin >> N;
    std::vector<std::vector<int>> g(N);
    for (int i = 0, u, v; i < N - 1; i++) {
        std::cin >> u >> v, u--, v--;
        g[u].push_back(v), g[v].push_back(u);
    }
    if (N <= 2) { return std::cout << 1 << std::endl, 0; }
    std::vector<int> LOG;
    auto dfs = [&](auto&& self, const int s, const int prev) -> void {
        for (const int to : g[s]) {
            if (to == prev) { continue; }
            LOG.push_back(1);
            self(self, to, s);
            LOG.push_back(-1);
        }
    };
    dfs(dfs, 0, -1);
    int d = 0;
    for (int i = 1; i < 2 * (N - 1); i++) {
        if (LOG[i - 1] != LOG[i]) { d++; }
    }
    (d -= 1) /= 2;
    N -= 2;
    ModCombination<> mod(2 * N);
    std::vector<ll> cat(2 * N + 1, 0);
    for (int i = 0; i <= N; i++) { cat[2 * i] = mod.combination(2 * i, i) * mod.inverse(i + 1) % MOD; }
    std::vector<ll> coeff(N + 1, 0);
    for (int i = 0; i <= N; i += 2) { coeff[i] = mod.combination(N, i) * cat[i] % MOD; }
    ll ans = 0;
    for (int i = 0; i <= 2 * d; i += 2) {
        if (N - i < d - i / 2) { break; }
        (ans += mod.combination(N - i, d - i / 2) * coeff[i] % MOD) %= MOD;
    }
    std::cout << ans << std::endl;
    return 0;
}