import random

class Sheet(object):
    def __init__(self, seed=None, entries=()):
        self.seed = seed
        self.entries = entries

    @classmethod
    def generate(cls, lowest_factor, highest_factor, total=100, seed=None):
        entries = []
        for f0 in range(lowest_factor, highest_factor):
            for f1 in range(lowest_factor, highest_factor):
                entries.append(((f0, f1), f0 * f1))
        random.seed(seed)
        random.shuffle(entries)
        return cls(seed=seed, entries=entries)