b = c.get_bucket(bucket, validate=False)
url = 'http://en.wikipedia.org/static/images/project-logos/enwiki.png'
r = requests.get(url)
if r.status_code == 200:
    k = Key(b)
k.key = 'image1.png'
k.content_type = r.headers['content-type']
k.set_contents_from_string(r.content)
How to upload a file to S3 without creating a temporary local file