Write the web app to prompt accepting for positive integers until the user
enters a negative integer
If the entered text is not a positive integer number, then the web app
will keep asking for a number until the valid positive integer is
entered
If the entered text is a negative integer, then the web app will show
the statistics (average, min, max) of all entered positive integers
Note:
You need to implement functions to check whether an external text is a
positive integer or not and whether an entered text is a negative
integer or not
You need to implement functions to compute average, min, and max of a
list of integers