from collections import deque
MOD = 10**9 + 7
inpl = lambda: list(map(int,input().split()))
N = int(input())
children = [set() for _ in range(N)]
parent = [None] * N
for _ in range(N-1):
    A, B = inpl()
    A, B = A-1, B-1
    children[A].add(B)
    parent[B] = A
depth=[-1]*N
root = parent.index(None)
ans = 0
pool = deque([root])
depth[root]=0
while pool:
    node = pool.popleft()
    ans += depth[node] * (depth[node]+1) // 2
    for c in children[node]:
        if depth[c]!=-1:continue
        depth[c]=depth[node]+1
        pool.append(c)

print(ans%MOD)