how to return the keys returned from a boto3 function code example
Example: upload_file boto3 headers
import boto3
s3 = boto3.resource('s3')
s3.meta.client.upload_file('source_file_name.html', 'my.bucket.com', 'aws_file_name.html', ExtraArgs={'ContentType': "application/json", 'ACL': "public-read"} )