'Download torrent using a file.
:param file_buffer: Single file() buffer or list of.
:param save_path: Path to download the torrent.
:param label: Label of the torrent(s). qbittorrent < 3.3.5
:param category: Label of the torrent(s). qbittorrent >= 3.3.5
:return: Empty JSON data.'

def download_from_file(self, file_buffer, save_path=None, label=''):

    if isinstance(file_buffer, list):
        torrent_files = {}
        for (i, f) in enumerate(file_buffer):
            torrent_files.update({('torrents%s' % i): f})
        print torrent_files
    else:
        torrent_files = {'torrents': file_buffer}
    data = {}
    if save_path:
        data.update({'savepath': save_path})
    if ((self.api_version < 10) and label):
        data.update({'label': label})
    elif ((self.api_version >= 10) and label):
        data.update({'category': label})
    return self._post('command/upload', data=data, files=torrent_files)
