Detecting Specific Sounds (Frequencies) with Python

Question

I want to record sound of a machine and want to detect if its present in another sound file that I record. I am able to record the sound of the machine and the sound file that I want to detect its presence.

I am also able to take fft of the sound files, however I dont know If I should check specific frequencies or check it in time intervals. Can I implement it with aubio or is there another way?

silent room silent room + sound