import torch


def linreg(X, w, b):
    """
    Return the matrix multiply result of X*w+b

    Parameters
    ----------
    X : [tensor]
        the variablies of the question
    w : [tensor]
        the weight of this linear reg
    b : [tensor]
        the bias of this linear reg

    Returns
    -------
    [tensor]
        the matrix multiply result of X*w+b
    """
    # mm means matrix multiply
    return torch.mm(X, w)+b