Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def LS(): return list(map(list, input().split()))
def S(): return list(input().rstrip())
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    edg = [[] for i in range(n)]
    t = 0
    ab = defaultdict(int)
    d = defaultdict(int)
    for _ in range(n - 1):
        a, b = LI_()
        edg[a].append(b)
        edg[b].append(a)
        d[(a, b)] = t
        d[(b, a)] = t
        t += 1
    m = II()
    path = [0] * m 
    uv = LIR_(m)
    for i, uvi in enumerate(uv):
        u, v = uvi
        q = deque()
        q.append((u, []))
        while q:
            p, pat = q.popleft()
            for e in edg[p]:
                if e in pat:
                    continue
                if e == v:
                    pat += [d[(p, e)]]
                    q = deque()
                    break
                else:
                    q.append((e, pat + [d[(p, e)]]))
        for p in pat:
            path[i] |= 1 << p
    ans = 1 << (n-1)
    for mask in range(1, 1 << m):
        tmp = 0
        t = 0
        for i in range(m):
            if mask & (1 << i):
                t += 1
                tmp = tmp | path[i]
        x = 0
        while tmp:
            x += tmp & 1
            tmp >>=1
        ans += (1 << (n - x - 1)) * (-1) ** t
    print(ans)


    return


#main
if __name__ == '__main__':
    solve()


Fixed submission:
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def LS(): return list(map(list, input().split()))
def S(): return list(input().rstrip())
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    def dfs(p, g, pre=-1):
        for e in edg[p]:
            if e == pre: continue
            if e == g:
                return [d[(p, e)]]
            tmp = dfs(e, g, p)
            if tmp:
                return tmp + [d[(p, e)]]
        return False

    n = II()
    edg = [[] for i in range(n)]
    t = 0
    ab = defaultdict(int)
    d = defaultdict(int)
    for _ in range(n - 1):
        a, b = LI_()
        edg[a].append(b)
        edg[b].append(a)
        d[(a, b)] = t
        d[(b, a)] = t
        t += 1
    m = II()
    path = [0] * m 
    uv = LIR_(m)
    for i, uvi in enumerate(uv):
        u, v = uvi
        pat = dfs(u,v)
        for p in pat:
            path[i] |= 1 << p
    ans = 1 << (n - 1)
    for mask in range(1, 1 << m):
        tmp = 0
        t = 0
        for i in range(m):
            if mask & (1 << i):
                t += 1
                tmp = tmp | path[i]
        x = 0
        while tmp:  
            x += tmp & 1
            tmp >>=1
        ans += (1 << (n - x - 1)) * (-1) ** t
    print(ans)


    return


#main
if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def LS(): return list(map(list, input().split()))
def S(): return list(input().rstrip())
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    edg = [[] for i in range(n)]
    t = 0
    ab = defaultdict(int)
    d = defaultdict(int)
    for _ in range(n - 1):
        a, b = LI_()
        edg[a].append(b)
        edg[b].append(a)
        d[(a, b)] = t
        d[(b, a)] = t
        t += 1
    m = II()
    path = [None] * m 
    uv = LIR_(m)
    for i, uvi in enumerate(uv):
        u, v = uvi
        q = deque()
        q.append((u, []))
        while q:
            p, pat = q.popleft()
            for e in edg[p]:
                if e in pat:
                    continue
                if e == v:
                    pat += [d[(p, e)]]
                    q = deque()
                    break
                else:
                    q.append((e, pat + [d[(p, e)]]))
        path[i] = set(pat)
    ans = 1 << (n-1)
    for mask in range(1, 1 << m):
        tmp = set()
        t = 0
        for i in range(m):
            if mask & (1 << i):
                t += 1
                tmp = tmp | path[i]
        ans += (1 << (n - len(tmp) - 1)) * (-1) ** t
    print(ans)


    return


#main
if __name__ == '__main__':
    solve()


Fixed submission:
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def LS(): return list(map(list, input().split()))
def S(): return list(input().rstrip())
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    def dfs(p, g, pre=-1):
        for e in edg[p]:
            if e == pre: continue
            if e == g:
                return [d[(p, e)]]
            tmp = dfs(e, g, p)
            if tmp:
                return tmp + [d[(p, e)]]
        return False

    n = II()
    edg = [[] for i in range(n)]
    t = 0
    ab = defaultdict(int)
    d = defaultdict(int)
    for _ in range(n - 1):
        a, b = LI_()
        edg[a].append(b)
        edg[b].append(a)
        d[(a, b)] = t
        d[(b, a)] = t
        t += 1
    m = II()
    path = [0] * m 
    uv = LIR_(m)
    for i, uvi in enumerate(uv):
        u, v = uvi
        pat = dfs(u,v)
        for p in pat:
            path[i] |= 1 << p
    ans = 1 << (n - 1)
    for mask in range(1, 1 << m):
        tmp = 0
        t = 0
        for i in range(m):
            if mask & (1 << i):
                t += 1
                tmp = tmp | path[i]
        x = 0
        while tmp:  
            x += tmp & 1
            tmp >>=1
        ans += (1 << (n - x - 1)) * (-1) ** t
    print(ans)


    return


#main
if __name__ == '__main__':
    solve()