L = [('Bob', 75), ('Adam', 92), ('Bart', 66), ('Lisa', 88)]

def by_name(t):

a=t[0]

return a

L2 = sorted(L, key=by_name)

print(L2)

第二题

L = [('Bob', 75), ('Adam', 92), ('Bart', 66), ('Lisa', 88)]

def by_score(t):

a=t[1]

return a

L2 = sorted(L, key=by_score)

print(L2)