from __future__ import annotations

from abc import ABC


class MaterialsRepository(ABC):
    """Loads the retrofit Materials catalogue the Modelling stage draws measures
    and costs from.

    Seam only at this stage (#1136): the method shape is deferred to the
    Modelling per-service grill. Declared now so the pipeline can be composed
    end-to-end with Modelling stubbed.
    """