Could not recognize audio

import speech_recognition as sr r = sr.Recognizer() harvard = sr.AudioFile('jackhammer.wav') with harvard as source: r.adjust_for_ambient_noise(source) audio = r.record(source) type(audio) print(r.recognize_google(audio))

showning error:

File "/home/anil/.local/lib/python2.7/site-packages/speech_recognition/init.py", line 844, in recognize_google raise RequestError("recognition connection failed: {}".format(e.reason)) speech_recognition.RequestError: recognition connection failed: [Errno -2] Name or service not known