Exercise: Basic Python

Build a small module that models task status transitions and overdue checks for a release tracker. Everything fits in a single main.py.

1. Define a TaskStatus enum with members planned, in_progress, blocked, and done. Use StrEnum so the values are strings.

   Python

   from enum import StrEnum
   
   
   class TaskStatus(StrEnum):
       planned = "planned"
       in_progress = "in_progress"
       blocked = "blocked"
       done = "done"
   

2. Write is_overdue(due_date, status) that returns True only when the task has a due date, isn't done, and the due date is in the past. Otherwise return False.

   Python

   def is_overdue(due_date, status):
       pass
   

3. Write next_status(current) that advances the task's state. planned becomes in_progress, in_progress becomes done, and done and blocked stay where they are.

   Python

   def next_status(current):
       match current:
           case TaskStatus.planned:
               pass  # TODO
           case TaskStatus.in_progress:
               pass  # TODO
           case TaskStatus.done | TaskStatus.blocked:
               pass  # TODO
   

4. Put this at bottom of to call the sample inputs and prints the results.

   Python

   from datetime import date, timedelta
   
   if __name__ == "__main__":
       yesterday = date.today() - timedelta(days=1)
   
       print(is_overdue(None, TaskStatus.planned))  # False
       print(is_overdue(yesterday, TaskStatus.done))  # False
       print(is_overdue(yesterday, TaskStatus.in_progress))  # True
   
       print(next_status(TaskStatus.planned))  # TaskStatus.in_progress
       print(next_status(TaskStatus.in_progress))  # TaskStatus.done
       print(next_status(TaskStatus.done))  # TaskStatus.done
       print(next_status(TaskStatus.blocked))  # TaskStatus.blocked
   

Run the file with uv run main.py and confirm the output matches the comments.

Solution

Python

from datetime import date, timedelta
from enum import StrEnum


class TaskStatus(StrEnum):
    planned = "planned"
    in_progress = "in_progress"
    blocked = "blocked"
    done = "done"


def is_overdue(due_date, status):
    if due_date is None:
        return False
    if status == TaskStatus.done:
        return False
    return due_date < date.today()


def next_status(current):
    match current:
        case TaskStatus.planned:
            return TaskStatus.in_progress
        case TaskStatus.in_progress:
            return TaskStatus.done
        case TaskStatus.done | TaskStatus.blocked:
            return current


if __name__ == "__main__":
    yesterday = date.today() - timedelta(days=1)

    print(is_overdue(None, TaskStatus.planned))  # False
    print(is_overdue(yesterday, TaskStatus.done))  # False
    print(is_overdue(yesterday, TaskStatus.in_progress))  # True

    print(next_status(TaskStatus.planned))  # TaskStatus.in_progress
    print(next_status(TaskStatus.in_progress))  # TaskStatus.done
    print(next_status(TaskStatus.done))  # TaskStatus.done
    print(next_status(TaskStatus.blocked))  # TaskStatus.blocked

Success

If the driver prints the values shown in the comments next to each print call, the enum, conditional, and match-statement work as expected