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How to Build a Chainable Filter Helper in Python

A beginner-friendly dataclass helper that chains filters, uniqueness, and slicing on any sequence, returning a plain list at the end.

dataclass chaining filter
Python 
from dataclasses import dataclass
from typing import Callable, Iterator, Sequence, TypeVar

T = TypeVar("T")


@dataclass
class FilterAssistant:
    """Beginner-friendly helper to filter any collection."""

    data: Sequence[T]

    def where(self, predicate: Callable[[T], bool]) -> "FilterAssistant":
        return …
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