code: def z_rotate(rotationAmt):
          
          ma4 = Matrix4((math.cos(rotationAmt), -math.sin(rotationAmt), 0, 0),
                        (math.sin(rotationAmt), math.cos(rotationAmt), 0, 0),
                        (0, 0, 1, 0),
                        (0, 0, 0, 1))
  
          return ma4
docs: Create a matrix that rotates around the z axis.