def translation_matrix(direction):
M = numpy.identity(<NUM_LIT:4>)<EOL>M[:<NUM_LIT:3>, <NUM_LIT:3>] = direction[:<NUM_LIT:3>]<EOL>return M<EOL>
Return matrix to translate by direction vector.

    >>> v = numpy.random.random(3) - 0.5
    >>> numpy.allclose(v, translation_matrix(v)[:3, 3])
    True