import torch


def build_scheduler(optimiser, learning_rate_decay):
    """
    Instantiate the scheduler of the learning rate
    :param optimiser: the associated optimiser
    :param learning_rate_decay: value of the learning rate decay
    :return: scheduler instance
    """
    scheduler = torch.optim.lr_scheduler.ExponentialLR(optimiser, gamma=learning_rate_decay)

    return scheduler