tester.py

import pyaudio
import wave
from pynput import keyboard

FORMAT = pyaudio.paInt16
CHANNELS = 2
RATE = 44100
CHUNK = 1024
RECORD_SECONDS = 5
WAVE_OUTPUT_FILENAME = "output.wav"

frames = []

def on_press(key):
    global frames
    if key.char == 'a':
        print("Inside...")
        # Start recording
        audio = pyaudio.PyAudio()
        stream = audio.open(format=FORMAT, channels=CHANNELS,
                            rate=RATE, input=True,
                            frames_per_buffer=CHUNK)
        print("Recording audio...")
        while True:
            data = stream.read(CHUNK)
            frames.append(data)
            if keyboard.is_pressed('esc'):
                break
        stream.stop_stream()
        stream.close()
        audio.terminate()

def on_release(key):
   if key == keyboard.Key.esc:
       # Stop recording
       audio = pyaudio.PyAudio()
       stream = audio.open(format=FORMAT, channels=CHANNELS,
                           rate=RATE, input=True,
                           frames_per_buffer=CHUNK)
       stream.stop_stream()
       stream.close()
       audio.terminate()
       print("Finished recording audio.")
       # Save recorded audio data to a .wav file
       wf = wave.open(WAVE_OUTPUT_FILENAME, 'wb')
       wf.setnchannels(CHANNELS)
       wf.setsampwidth(audio.get_sample_size(FORMAT))
       wf.setframerate(RATE)
       wf.writeframes(b''.join(frames))
       wf.close()
       # Stop the listener
       return False

# Start the listener
with keyboard.Listener(on_press=on_press, on_release=on_release) as listener:
    listener.join()