code: def translation_matrix(direction):
      """Return matrix to translate by direction vector.
  
      >>> v = numpy.random.random(3) - 0.5
      >>> numpy.allclose(v, translation_matrix(v)[:3, 3])
      True
  
      """
      M = numpy.identity(4)
      M[:3, 3] = direction[:3]
      return M
  
imports: import math
  import numpy
label_desc: Use image node_id 2 for calling a global function with example usage: translation_matrix(direction) and returns: M