Implement total_income

from pathlib import Path

from itertools import chain

from dataclasses import dataclass

from typing import Self

from decimal import Decimal

    @property

    def total_income(self) -> Decimal:

        pass

        # Assignments (Zuweisungen) and reserves (Rücklagen) is the only kind of income we automatically get

        assignments = self.budget_plan.group("1")

        reserves = self.budget_plan.group("3")

        return sum(

            item.amount for item in chain(

                assignments.items if assignments else [],

                reserves.items if reserves else []

            )

        )

    @property

    def total_expenses(self) -> Decimal: