title: Error in joblib.load when reading file from s3
body: <p>When trying to read a file from s3 with <code>joblib.load()</code> I get the error <code>ValueError: embedded null byte</code> when attempting to read files.  </p>
  
  <p>The files were created by joblib and can be successfully loaded from local copies (that were made locally before uploading to s3), so the error is presumably in storage and retrieval protocols from S3.</p>
  
  <p>Min code:</p>
  
  <pre><code>####Imports (AWS credentials assumed)
  import boto3
  from sklearn.externals import joblib
  
  
  s3 = boto3.resource('s3')
  bucket_str = "my-aws-bucket"
  bucket_key = "some-pseudo/folder-set/my-filename.joblib"
  joblib.loads(s3.Bucket(bucket_str).Object(bucket_key).get()['Body'].read())
  </code></pre>