SafariReadingListToPinboard.py

import subprocess
from pathlib import Path
import plistlib
import pinboard  # install via pip
from shutil import which

PINBOARD_TOKEN = "< your pinboard token>"

subprocess.check_call(
    [
        which("plutil"),
        "-convert",
        "xml1",
        "-o",
        "/tmp/Bookmarks.plist",
        Path("~/Library/Safari/Bookmarks.plist").expanduser(),
    ]
)

bookmarks = plistlib.load(open("/tmp/Bookmarks.plist", "rb"))

groups = [
    group
    for group in bookmarks["Children"]
    if group["Title"] == "com.apple.ReadingList"
]
reading_list = groups[0]
reading_list_items = reading_list.get("Children", [])

bookmarks = [
    (item["URLString"], item["URIDictionary"]["title"]) for item in reading_list_items
]

pb = pinboard.Pinboard(PINBOARD_TOKEN)

for url, title in bookmarks:
    print(url)
    result = pb.posts.add(
        url=url,
        description=title if title else "Untitled",
        tags="SafariReadingList",
        shared=False,
        toread=True,
    )
    print(result)