'Set file of a torrent to a supplied priority level.
:param infohash: INFO HASH of torrent.
:param file_id: ID of the file to set priority.
:param priority: Priority level of the file.'

def set_file_priority(self, infohash, file_id, priority):

    if (priority not in [0, 1, 2, 7]):
        raise ValueError('Invalid    priority,    refer    WEB-UI    docs    for    info.')
    elif (not isinstance(file_id, int)):
        raise TypeError('File    ID    must    be    an    int')
    data = {'hash': infohash.lower(), 'id': file_id, 'priority': priority}
    return self._post('command/setFilePrio', data=data)
