• Write a Python program that will compute the corresponding grade based on the average test score.
• This program must consist of three functions as indicated below.

• readScore
  • This function will prompt the user to enter the score and return a legitimate score.
  • Any number outside the range of 0 to 100 is not legitimate score.
• checkGrade
  • This function should accept three test scores as parameters and return the grade based on Table 1.
• displayGrade
  • This function should accept a grade as parameter and prints the grade and its corresponding grade-message based on the Table 1.

Average Test Scores	Grade Message
90 --- 100	Excellent student
80 --- 89	Good student
60--- 79	Normal student
Below 59	Fail