# 生成一些随机数据
for i in range(100):
    if np.random.rand() < 0.5:
        df.loc[i] = ['工序1', np.random.randint(1, 31)]
    else:
        df.loc[i] = ['工序2', np.random.randint(1, 31)]

随机(50%概率)分配数据到工序1或工序2