todo-app.py

# This is just a little draft with two rather obvious classes you might need to have at the beginning.
# 
#
# At first glance I see three ways of implementing TodoEntry class,
# speaking about how field are stored in it
# It seams this class would not have much functionality,
# mostly just storing fields, marking entry completed autoinsresting 'completedData',
# something more, and not much data integrity checking,
# so I prefer the last variant, it's faster and seams more attractive (for me) to implement 

class TodoEntry:
    """ Some internal todo entry storage format, independent of todo system """
    def __init__(self):
        self.data = {
            'id': None,
            'title': None,
            'createdDate': None
        }
        # or shorter
        self.data = {}
        default_fields = ['id', 'title', 'createdData']
        for field in default_fields:
            self.data[field] = None

    def mark_done(self):
        pass

    def __str__(self):
        # some to str convertion for developer's needs
        pass

# OR

class TodoEntry:
    def __init__(self):
        self.id = None
        self.title = None
        self.createdData = None

# OR

class TodoEntry(dict):
    pass


class TodoList:
    def __init__(self):
        self.entries = []

    def import_from_todo_txt(text):
        pass

    def import_from_orgmode(text):
        pass

    def export_to_todo_txt():
        pass

    def export_to_orgmode():
        pass


if __name__ == '__main__':
    todo = TodoList()
    with open('todo.txt') as ff:
        todo.import_from_todo_txt(ff.read())
    with open('todo.org', 'w') as ff:
        ff.write(todo.export_to_orgmode())