PyAudio home page:http://people.csail.mit.edu/hubert/pyaudio
There is download links and install instructions for windows/OSX/linux.
Following is the code for the audio transmission between server and client in one direction. First the client records the audio from the mic and store in a buffer and then transmit by TCP socket. The server receives the data and play out by speaker.
import socket import pyaudio import wave #record CHUNK = 1024 FORMAT = pyaudio.paInt16 CHANNELS = 1 RATE = 44100 RECORD_SECONDS = 40 HOST = '' # The remote host PORT = 50007 # The same port as used by the server s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.connect((HOST, PORT)) p = pyaudio.PyAudio() stream = p.open(format=FORMAT, channels=CHANNELS, rate=RATE, input=True, frames_per_buffer=CHUNK) print("*recording") frames =  for i in range(0, int(RATE/CHUNK*RECORD_SECONDS)): data = stream.read(CHUNK) frames.append(data) s.sendall(data) print("*done recording") stream.stop_stream() stream.close() p.terminate() s.close() print("*closed")
# Echo server program import socket import pyaudio import wave import time CHUNK = 1024 FORMAT = pyaudio.paInt16 CHANNELS = 1 RATE = 44100 RECORD_SECONDS = 4 WAVE_OUTPUT_FILENAME = "server_output.wav" WIDTH = 2 frames =  p = pyaudio.PyAudio() stream = p.open(format=p.get_format_from_width(WIDTH), channels=CHANNELS, rate=RATE, output=True, frames_per_buffer=CHUNK) HOST = '' # Symbolic name meaning all available interfaces PORT = 50007 # Arbitrary non-privileged port s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.bind((HOST, PORT)) s.listen(1) conn, addr = s.accept() print 'Connected by', addr data = conn.recv(1024) i=1 while data != '': stream.write(data) data = conn.recv(1024) i=i+1 print i frames.append(data) wf = wave.open(WAVE_OUTPUT_FILENAME, 'wb') wf.setnchannels(CHANNELS) wf.setsampwidth(p.get_sample_size(FORMAT)) wf.setframerate(RATE) wf.writeframes(b''.join(frames)) wf.close() stream.stop_stream() stream.close() p.terminate() conn.close()
In the server part, I store the received audio into an wav file just for record. If you want to do voice chat, you can add another process and deal with the echo cancellation. Also for better audio quality and noise reduction, you may add threshold at the client. Also for better performance under worse network situation, you may need to try compress the audio before transmission.