I sent this email this morning but it didn't seem to make it through, so I'm sending it again. My appologies if it eventually becomes a duplicate:
 
Hello. In the modLua documentation (pasted below),  it suggests in the comment that recordings using recordFile may be ended by pressing the # key. For Python, the documentation for the API points to modLua, but the touch-tone barge-in doesn't seem to be working for me. And I can't figure out a simple way to accomplish this. Any advice?
session:recordFilesyntax is session:recordFile(file_name, max_len, silence_threshold, silence_secs) Example: 
session:recordFile("/tmp/blah.wav", 30000, 10, 10);  -- pressing # ends the recording                                                                                                           
session:streamFile("/tmp/blah.wav"); 