def METHOD_NAME(a_int32):
    """convert int32 values into int4
    Parameters
    ----------
    a_int32 : int
    Return
    ------
    a_int4 : int
    """
    K, L = a_int32.shape
    assert L % 8 == 0
    a_int4 = np.zeros(shape=(K, L // 8), dtype=np.int32)
    for k in range(K):
        for l in range(L // 8):
            for m in range(min(8, L - l * 8)):
                a_int4[k, l] = a_int4[k, l] | ((a_int32[k, l * 8 + m] & 0xF) << ((7 - m) * 4))
    return a_int4