How to Load and Inspect CSV Data with a Dataclass Helper in Python

from pathlib import Path
from dataclasses import dataclass
from typing import Any


@dataclass
class DataHelper:
    """Simple helper for loading and inspecting CSV data."""
    filepath: Path

    def load_csv(self, *, delimiter: str = ",") -> list[dict[str, Any]]:
        """Read CSV into a list of dictionaries."""
        import csv
        with self.filepath.open(newline="") as f:
            reader = csv.DictReader(f, delimiter=delimiter)
            return [dict(row) for row in reader]

    def describe(self, data: list[dict[str, Any]]) -> None:
        """Print basic information about the dataset."""
        if not data:
            print("Dataset is empty.")
            return
        columns = list(data[0].keys())
        print(f"Rows: {len(data)}")
        print(f"Columns: {columns}")
        print("Sample row:", data[0])


if __name__ == "__main__":
    import tempfile
    sample = Path("sample_data.csv")
    sample.write_text("name,age,city\nAlice,30,Berlin\nBob,25,Paris\n", encoding="utf-8")

    helper = DataHelper(sample)
    dataset = helper.load_csv()
    helper.describe(dataset)

    sample.unlink(missing_ok=True)