title: Uploading asset to S3 isn't working
body: <p>I need to upload a css file and a js file to S3 and use them as static resources. If I upload them via web from S3 page, it works. But if I upload via a python script, it uploads the files, but I can't get the css seems not working at all.</p>
  
  <p>Here is my python code,</p>
  
  <pre><code>s3 = boto3.resource('s3')
  s3.meta.client.upload_file('sample.css', 'mybucket', 'sample_dir/sample.css', {'ACL': 'public-read'})
  </code></pre>