def matrix(*args):
    """Input arguments as rows in list form to construct a functional matrix.
    
    >>> row1, row2 = row(1, 0), row(0, 1)
    >>> matrix(row1, row2)
    [[1, 0], [0, 1]]
    """
    a = []
    for arg in args:
        a.append(arg)
    return a
