https://github.com/eHanlin/memcached-session-manager/tree/1.8.3-base64 is the same encoder and decoder.
python setup.py install
Decode binary from ascii list.
buffers = map( ord, session_str )
data = transcoder.deserialize( buffers )
Encode dict into ascii list.
data["principalData"]["pythonttest"] = "123344"
transcoder.serialize( data )
import base64
import pylibmc
from msm_transcoder import Transcoder
mc = pylibmc.Client(["127.0.0.1"], binary=True)
session_str = base64.b64decode( session )
buffers = map( ord, session_str )
transcoder = Transcoder()
data = transcoder.deserialize( buffers )
data["principalData"]["pythonttest"] = "123344"
output = base64.b64encode( ''.join( map( chr, transcoder.serialize( data ) ) ) )
mc.set( sessionId , output)