from haystack import Document
from haystack.components.retrievers.in_memory import InMemoryBM25Retriever
from haystack.document_stores.in_memory import InMemoryDocumentStore
from haystack.document_stores.types import FilterPolicy


document_store = InMemoryDocumentStore(
    bm25_algorithm="BM25Plus",
    bm25_parameters={"k1": 1.2, "b": 0.75, "delta": 0.5},
)