[Python] How to Reliably Detect a Specific USB Device (Ancel OBD2 Scanner) in Python Using...

I'm working on automating firmware updates for an Ancel OBD2 scanner using Python. The first step in the process is to reliably detect when the device is connected via USB. The official process is described here:

So far, I've been using pyusb to list connected USB devices. Here's a snippet of what I'm doing:

import usb.core
import usb.util

# Example vendor and product IDs — may not be correct yet
dev = usb.core.find(idVendor=0x1234, idProduct=0x5678)

if dev is None:
print("Device not found")
else:
print("Device detected")


The problem is:

The scanner is not always detected, even though it shows up under /dev (on Linux) or Device Manager (on Windows). Sometimes I need to reconnect it multiple times for detection to succeed.

I have tried matching different idVendor/idProduct pairs based on system inspection. What is the most reliable way to detect a specific USB device (like the Ancel OBD2 scanner) in Python, especially if the mount behavior or enumeration is inconsistent?

If there's a better approach than pyusb (e.g., using libusb, pyudev, or even polling /dev), I’m open to suggestions.

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