Get the last lines from a file

last_lines.py

import mmap


def get_last_lines(path: str, count: int) -> list[str]:
    """Get count last lines from a file."""
    with open(path, "r+b") as text_file:
        text_mmap = mmap.mmap(text_file.fileno(), 0, mmap.ACCESS_READ)
        position = len(text_mmap)
        while count and (position := text_mmap.rfind(b"\n", 0, position)) != -1:
            count -= 1
        return text_mmap[position + 1 :].decode("utf-8").split("\n")


if __name__ == "__main__":

    import sys

    last = get_last_lines(sys.argv[1], 5)
    print(last)
    print(len(last))