title: S3: ExpiredToken error for S3 pre-signed url within expiry period
body: <p>This is how I am generating pre-signed url for an S3 object from my python script.</p>
  
  <pre><code>s3client = boto3.client("s3")
  url = s3client.generate_presigned_url("get_object", Params={"Bucket": args.bucket, "Key": dated_filename}, ExpiresIn=86400)
  </code></pre>
  
  <p>where I am giving an expiry of 24 hours. </p>
  
  <p>When I try to download the file immediately using the url from a browser, it works. But it doesn't work if I try to download it, say after 10-12 hours (I don't know the exact time after which it starts failing).</p>
  
  <p>This is the error I am getting.</p>
  
  <pre><code>&lt;Code&gt;ExpiredToken&lt;/Code&gt;
  &lt;Message&gt;The provided token has expired.&lt;/Message&gt;
  </code></pre>
  
  <p>Not sure if it is a bug or I am not doing it the right way. Any help would be appreciated.</p>