For this assignment, we'll be working with a national park planner-style domain.

We have three models: NationalPark, Visitor, and Trip.

For our purposes, a NationalPark has many Trips, a Visitor has many Trips, and a Trip belongs to a Visitor and to a NationalPark.

NationalPark - Visitor is a many to many relationship.

Note: You should draw your domain on paper or on a whiteboard before you start coding. Remember to identify a single source of truth for your data.

• Classes and Instances
• Class and Instance Methods
• Variable Scope
• Object Relationships
• lists and list Methods

To get started, run pipenv install while inside of this directory. Then run pipenv shell to jump into the shell.

Build out all of the methods listed in the deliverables. The methods are listed in a suggested order, but you can feel free to tackle the ones you think are easiest. Be careful: some of the later methods rely on earlier ones.

Remember! This code challenge has tests to help you check your work. You can run pytest to make sure your code is functional before submitting.

We've provided you with a tool that you can use to test your code. To use it, run python debug.py from the command line. This will start a ipdb session with your classes defined. You can test out the methods that you write here. You can add code to the debug.py file to define variables and create sample instances of your objects.

Writing error-free code is more important than completing all of the deliverables listed - prioritize writing methods that work over writing more methods that don't work. You should test your code in the console as you write.

Similarly, messy code that works is better than clean code that doesn't. First, prioritize getting things working. Then, if there is time at the end, refactor your code to adhere to best practices. When you encounter duplicated logic, extract it into a shared helper method.

Before you submit! Save and run your code to verify that it works as you expect. If you have any methods that are not working yet, feel free to leave comments describing your progress.

Write the following methods in the classes in the files provided. Feel free to build out any helper methods if needed.

• Visitor __init__(self, name)
  • Visitor is initialized with a name
• Visitor property name
  • Returns the visitor's name
  • Names must be of type str
  • Names must be between 1 and 15 characters, inclusive
  • Should be able to change after the visitor is instantiated

• NationalPark __init__(self, name)
  • NationalPark is initialized with a name, as a string
• NationalPark property name
  • Returns the national_park's name
  • Names must be of type str
  • Names length must be greater or equal to 3 characters
  • Should not be able to change after the national_park is instantiated
  • hint: hasattr()

• Trip __init__(self, visitor, national_park, start_date, end_date)
  • Trip is initialized with a Visitor instance, a NationalPark instance, a start_date, and an end_date
• Trip property start_date
  • Returns the trip's start_date
  • Start_date must be of type str
  • Start_date length must be greater or equal to 7 characters
  • Is in the format "September 1st"
  • Should be able to change after the trip is instantiated
• Trip property end_date
  • Returns the trip's end_date
  • End_date must be of type str
  • End_date length must be greater or equal to 7 characters
  • Is in the format "September 1st"
  • Should be able to change after the trip is instantiated

• Trip property visitor
  • Returns the Visitor object for that trip
  • Must be of type Visitor
• Trip property national_park
  • Returns the NationalPark object for that trip
  • Must be of type NationalPark

• Visitor trips()
  • Returns a list of all trips for that visitor
  • Trips must be of type Trip
• Visitor national_parks()
  • Returns a unique list of all parks that visitor has visited
  • Parks must be of type NationalPark

• NationalPark trips()
  • Returns a list of all trips at a particular national park
  • Trips must be of type Trip
• NationalPark visitors()
  • Returns a unique list of all visitors a particular national park has welcomed
  • Visitors must be of type Visitor

• NationalPark total_visits()
  • Returns the total number of times a park has been visited
  • Returns 0 if the park has no visits
• NationalPark best_visitor()
  • Returns the Visitor instance that has visited that park the most
  • Returns None if the park has no visitors

• Visitor total_visits_at_park(park)
  • Receives a NationalPark object as argument
  • Returns the total number of times a visitor visited the park passed in as argument
  • Returns 0 if the visitor has never visited the park

• NationalPark classmethod most_visited()
  • Returns the NationalPark instance with the most visits.
  • Returns None if there are no visits.
  • hint: will need a way to remember all NationalPark objects
  • hint: do you have a method to get the total visits for a particular NationalPark object?
  • Uncomment lines 127-135 in the national_park_test file

• First, comment out the following lines
  • national_park_test.py
    • lines 34-35
  • visitor_test.py
    • lines 23-24, 40-41, and 44-45
  • trip_test.py
    • lines 35-36, 49-50, 78-79, and 92-93
• Then, uncomment the following lines in the test files
  • national_park_test.py
    • lines 22-23, 26-27, and 38-39
  • visitor_test.py
    • lines 31-32, 48-49, 52-53
  • trip_test.py
    • lines 39-40, 53-54, 82-83, 96-97