from typing import Tuple


def parse_content_range(content_range: str, file_size: int) -> Tuple[int, int]:
    """Parse 'Range' header into integer interval."""
    content_range = content_range.strip().lower()
    content_ranges = content_range.split("=")[-1]
    range_start, range_end, *_ = map(str.strip, (content_ranges + "-").split("-"))
    return (
        max(0, int(range_start)) if range_start else 0,
        min(file_size - 1, int(range_end)) if range_end else file_size - 1,
    )