uses Tautulli as an easy way to get plex session data. has to be run on the same machine as your discord desktop client for access to RPC

discord_presence_plex.py

from pypresence import Presence # https://github.com/qwertyquerty/pypresence
from requests import get
from time import sleep
from sys import exit

client_id = "556909532417228919"
user = "blha303"
tautulli_instance = "https://tau.home.b303.me" # https://github.com/Tautulli/Tautulli

RPC = Presence(client_id)
RPC.connect()

while 1:
    my = [s for s in get(tautulli_instance + "/get_activity").json()["sessions"] if s["user"] == user]
    if my:
        my = my[0]
        s = int(my["view_offset"])//1000
        m,s = divmod(s,60)
        h,m = divmod(m,60)
        my["view_offset"] = "{:02d}:{:02d}:{:02d}".format(h,m,s)
        RPC.update(details="{grandparent_title} ({studio}) {parent_title} - {title}".format(**my),
                   state="{state} | {view_offset} | {stream_video_width}x{stream_video_height}".format(**my))
    else:
        RPC.clear()
    sleep(15)