IMPORTANT:
   *** Your instructor will guide you through this exercise. ***
   
   Your instructor may ask you to watch the video
      called  TkinterPractice   as you do this exercise.
   
If your instructor asks you to watch the video(s), it will:
1. Explain m1e, then ask you to do _TODO_'s 1 and 2 in m6.
2. Explain m2e, then ask you to do _TODO_'s 3 and 4 in m6.
3. Explain m3e, then ask you to do _TODO_ 5 in m6.
4. Explain m4e, then ask you to do _TODO_'s 6 and 7 in m6.
4. Explain m5e, then ask you to do _TODO_ 8 (and optionally 9) in m6.