python - ' UnboundLocalError: local variable 'command' referenced before assignment '

Question

Here is the code. I am making a microphone class that recognize user voice. It gives me an UnboundLocalError. That happens when I add a return command to the mic_config() method.

    import speech_recognition as sr
    import pyaudio
    from speaker import Speaker


    class Microphone: 
       """Microphone class that represent mic and get user's voice..."""

        def __init__(self):
            """Initializing of class"""
            self.recognizer = sr.Recognizer()  # Voice recognizer
            self.microphone = sr.Microphone()  # Mic

        def mic_config(self):

            try:
               with self.microphone as source:  # Getting mic
               print('Listening...')
               voice = self.recognizer.listen(source)
               command = self.recognizer.recognize_google(voice, language='en-IN')  # Using google api
               print(command)  # Printing what user said

            except:  # Expecting errors
                  pass
            return command


     m1 = Microphone()  # just a test
     m1.mic_config()

Answer 1

Yeah as Carcigenicate said it is because command is only defined in the try block. This means that if there is an error then command is not defined. I don't know if it is just in the code you posted here but there is an indent error in the with statement

try:
    with self.microphone as source:
        print('Listening...')
        voice = self.recognizer.listen(source)
        command = self.recognizer.recognize_google(voice, language='en-IN')
        print(command)

except: 
    raise CustomError
    # or return None, command = None, etc just define command before the last line
    # or don't let the function reach the return command statement

return command