write python program that define two functions with proper function names: Function $1$: Prompt the user to enter the number of students. Ensure that the entered value is a validnumber $($at least $2$ students$)$ before it return number of students to the caller. In case an invalid numberis entered, keep asking until a valid number is provided. Function $2$: Calculate and display the percentage of $\text{'}$A$\text{'}$ grades for a student based on the number of 'A'scompared to the total number of grades. Main function: ask for number of students. Then for each student, prompt the user to enter their grade.Valid grades are $\text{'}$A$\text{'},\text{'}$B$\text{'},\text{'}$C$\text{'},\text{'}$D$\text{'},$ and $\text{'}$F$\text{'}$ only regardless of letter case. Your code should continue askingfor grades until a non$-$valid grade is given. Then it Identifies and displays "Outstanding student" for thosestudents who have more than $50\%\text{'}$A$\text{'}$ grades based on their total grades. Invoke proper user definedfunctions.For functions $1$ and $2$ above, provide at least three test cases including expected results to demonstrate thefunctions functionality. Also add main purpose, argument and return type as comments under function header.

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