Exercise 09-41:

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# Python From Scratch
# Author: Nilo Ney Coutinho Menezes
# Editora Novatec (c) 2010-2025 - LogiKraft 2025
# Site: https://pythonfromscratch.com
# ISBN: 978-85-7522-949-1 (Paperback), 978-85-7522-950-7 (hardcover), 978-85-7522-951-4 (ebook)
#
# File: chapter 09/exercise-09-41.py.py
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import sys
import itertools


def print_bytes(image, bytes_per_line=16):
    for b in itertools.batched(image, bytes_per_line):
        hex_view = " ".join([f"{v:02x}" for v in b])
        tview = "".join([chr(v) if chr(v).isprintable() else "." for v in b])
        print(f"{hex_view} {" " * 3 * (bytes_per_line - len(b))}{tview}")


if __name__ == "__main__":
    if len(sys.argv) != 4:
        print("Usage: python program.py file max_bytes bytes_per_line")
        sys.exit(1)

    file = sys.argv[1]
    max_bytes = int(sys.argv[2])
    bytes_per_line = int(sys.argv[3])

    with open(file, "rb") as f:
        image = f.read(max_bytes)

    print_bytes(image, bytes_per_line)