<Response>
    <Play>https://s3.amazonaws.com/plivocloud/Trumpet.mp3</Play>
</Response>
This example plays the audio file Trumpet.mp3 to the caller. Example Request 
from plivo import plivoxml

response = plivoxml.ResponseElement()
response.add(plivoxml.PlayElement('https://s3.amazonaws.com/Trumpet.mp3'))
print(response.to_string())

<Response>
    <Play>https://s3.amazonaws.com/plivocloud/Trumpet.mp3</Play>
</Response>