import sys
input=sys.stdin.readline

def dfs(start):
  global ans,mod
  stack = [start]
  depth = [-1]*N
  depth[start] = 0
  while stack:
    v = stack.pop()
    marker = 0
    for u in edge[v]:
      if depth[u]==-1: #前半
        marker = 1
        depth[u]=depth[v]+1
        ans += depth[u]*(depth[u]+1)//2
        ans %= mod
        stack.append(u)
  return

N = int(input())
mod = 10**9+7
edge = [[] for _ in range(N)]
roots = [True]*N
for i in range(N-1):
  a,b = list(map(int, input().split()))
  roots[b-1] = False
  edge[a-1].append(b-1)

root = roots.index(True)
ans = 0
dfs(root)
print(ans)