input: Write a python function to convert a magnitude and angle into a 3D vector.
  assert magnitude_to_vector(5, 90) == (0.0, 5.0, 0)
  assert magnitude_to_vector(10, 0) == (10.0, 0.0, 0)
  assert magnitude_to_vector(0, 45) == (0.0, 0.0, 0)
  assert magnitude_to_vector(5, 45) == (3.5355339059327378, 3.5355339059327373, 0)
output: def magnitude_to_vector(magnitude, angle):
      import math
      x = magnitude * math.cos(math.radians(angle))
      y = magnitude * math.sin(math.radians(angle))
      z = 0
      return (x, y, z)