from collections import namedtuple
Uni = namedtuple('Uni', ['num_student', 'num_groups'])
a = [(10, 4), (5, 3), (9, 5)]
def f(records):
    res = 0.0
    for r in records:
        s = Uni(*r)
        res += s.num_student * s.num_groups
    return res
print(f(a))