m: row
    n: column
    lst: items

    >>> print(_matrix(2, 3, [(1, 1), (2, 3)]))
    |x| | |
    | | |x|

def matrix(
        m, n, lst,
        m_text: list=None,
        n_text: list=None):
    """
    m: row
    n: column
    lst: items

    >>> print(_matrix(2, 3, [(1, 1), (2, 3)]))
    |x| | |
    | | |x|
    """

    fmt = ""
    if n_text:
        fmt += "     {}\n".format(" ".join(n_text))
    for i in range(1, m+1):
        if m_text:
            fmt += "{:<4.4} ".format(m_text[i-1])
        fmt += "|"
        for j in range(1, n+1):
            if (i, j) in lst:
                fmt += "x|"
            else:
                fmt += " |"
        fmt += "\n"
    return fmt