Update README.md

Fixed indentation

README.md

@@ -239,14 +239,11 @@ audio_url = AudioAsset("mary_had_lamb").url
 # Use base64 encoded audio in the payload
 def encode_audio_base64_from_url(audio_url: str) -> str:
     """Encode an audio retrieved from a remote url to base64 format."""
-
     with requests.get(audio_url) as response:
         response.raise_for_status()
         result = base64.b64encode(response.content).decode('utf-8')
-
     return result
 
-
 audio_base64 = encode_audio_base64_from_url(audio_url=audio_url)
 
 ### 1. Example with Audio