Add PaymentOrderCollection to aggregate

from dataclasses import dataclass

from pathlib import Path

from collections.abc import Iterable, Iterator

from ..utils import group_by

from .PaymentOrder import PaymentOrder

from .PaymentOrderLoader import load_pdf

@dataclass(frozen=True, eq=False)

class PaymentOrderCollection(Iterable[PaymentOrder]):

    base_dir: Path

    def __iter__(self) -> Iterator[PaymentOrder]:

        return (load_pdf(pdf) for pdf in self.base_dir.rglob("*.pdf"))

    @property

    def by_budgetary_item_id(self):

        return group_by(self, lambda payment_order: payment_order.budgetary_item_id)

import itertools

def group_by(iterable, key):

    return itertools.groupby(sorted(iterable, key=key), key)