code: def scale(scaleAmt):
          
          if not isinstance(scaleAmt, Vector3):
              raise ValueError("scaleAmt must be a Vector3")
  
          ma4 = Matrix4((scaleAmt.x, 0, 0, 0),
                        (0, scaleAmt.y, 0, 0),
                        (0, 0, scaleAmt.z, 0),
                        (0, 0, 0, 1))
          return ma4
docs: Create a scale matrix.
          scaleAmt is a Vector3 defining the x, y, and z scale values.