N = int(input())
G = [[] for _ in range(N+1)]
Gnum = [0] * (N + 1)
for _ in range(N-1):
    a,b = map(int,input().split())
    G[a].append(b)
    Gnum[b] += 1
root = -1
for i in range(1,N+1):
    if Gnum[i] == 0:
        root = i
        break
    

P = 10 ** 9 + 7
depth = [0] * (N + 1)
stack = [root]
ans = 0
while stack:
    now = stack.pop()
    for v in G[now]:
        depth[v] = depth[now] + 1
        ans = (ans + depth[v] * (depth[v] + 1) // 2) % P
        stack.append(v)
print(ans)