Plugin link:
plugin://plugin.video.jetproxy/play/http://oscartv.mine.nu:25461/live/jmr1234/jmr1234/6139.m3u8

Jen (jetextractors.py):
{
    "type": "item",
    "title": "JetProxy Test",
    "sportjetextractors": ["jetproxy://http://oscartv.mine.nu:25461/live/jmr1234/jmr1234/6139.m3u8"]
}

Jen (plug.py):
{
    "type": "plugin",
    "title": "JetProxy Plugin Test",
    "link": "RunPlugin(plugin://plugin.video.jetproxy/play/http://oscartv.mine.nu:25461/live/jmr1234/jmr1234/6139.m3u8)"
}

Python (xbmc.executebuiltin):
xbmc.executebuiltin("RunPlugin(plugin://plugin.video.jetproxy/play/http://oscartv.mine.nu:25461/live/jmr1234/jmr1234/6139.m3u8)")

Python (xbmc.Player)
xbmc.Player().play("plugin://plugin.video.jetproxy/play/http://oscartv.mine.nu:25461/live/jmr1234/jmr1234/6139.m3u8")