binorbin.py

import msgpack

class Event:
	@staticmethod
	def pack(payload):
		return msgpack.packb(payload, use_bin_type=True)

	@staticmethod
	def unpack(blob):
		return msgpack.unpackb(blob, raw=False, strict_map_key=False)

# >>> Event.unpack(Event.pack({1: 2}))
# {1: 2}

# >>> Event.unpack(Event.pack({'1': '2'}))
# {'1': '2'}

# server.py
import zmq
import msgpack

ctx = zmq.Context()
socket = ctx.socket(zmq.REP)
socket.bind("tcp://*:5555")

while True:
    req = msgpack.unpackb(socket.recv(), raw=False)
    print(f"Received: {req}")
    socket.send(msgpack.packb({'ok': True, 'echo': req}, use_bin_type=True))

# client.py
import zmq
import msgpack

ctx = zmq.Context()
socket = ctx.socket(zmq.REQ)
socket.connect("tcp://127.0.0.1:5555")

socket.send(msgpack.packb({'hello': 'world'}, use_bin_type=True))
reply = msgpack.unpackb(socket.recv(), raw=False)
print(reply)