'Get a library\'s watch time statistics.
Required parameters:
section_id (str):               The id of the Plex library section
Optional parameters:
None
Returns:
json:
[{"query_days": 1,
"total_plays": 0,
"total_time": 0
{"query_days": 7,
"total_plays": 3,
"total_time": 15694
{"query_days": 30,
"total_plays": 35,
"total_time": 63054
{"query_days": 0,
"total_plays": 508,
"total_time": 1183080'

@cherrypy.expose
@cherrypy.tools.json_out()
@requireAuth(member_of('admin'))
@addtoapi()
def get_library_watch_time_stats(self, section_id=None, **kwargs):

    if section_id:
        library_data = libraries.Libraries()
        result = library_data.get_watch_time_stats(section_id=section_id)
        if result:
            return result
        else:
            logger.warn(u'Unable    to    retrieve    data    for    get_library_watch_time_stats.')
    else:
        logger.warn(u'Library    watch    time    stats    requested    but    no    section_id    received.')
