How to detect APNGs sent in Discord using discord.py

Detect.py

import io

def is_apng(a: bytes) -> bool:
    acTL = a.find(b"\x61\x63\x54\x4C")
    if acTL > 0:
        iDAT = a.find(b"\x49\x44\x41\x54")
        if acTL < iDAT:
            return True
    return False


async def message_contains_apng(message: discord.Message) -> bool:
    for embed in message.embeds:
            if embed.type == "image":
                async with aiohttp.ClientSession() as session:
                    async with session.get(embed.url) as r:
                        try:
                            raw = await r.read()
                            if is_apng(raw):
                                return True
                        except Exception as e:
                            print(e)
                            return False

    for a in message.attachments:
        f = io.BytesIO()
        await a.save(f)
        if is_apng(f.read()):
            return True

    return False

LICENSE.md

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