def lr_scheduler(epochs):
    """Multiplies learning rate by 0.1 at 100 and 150 epochs, i.e.,
    new learning rate = old learning rate * 0.1"""

    switch_points = [0, 99, 149]
    for i in [2, 1, 0]:
        if epochs >= switch_points[i]:
            return 0.001 * pow(0.1, i) 
            #Learning rate is hyperparameters ==> start to 0.001 at epoch 0 and change at epoch n 100 and 150