code: def get_stream(self, rel_path, cb=None, return_meta=False):
          
          from boto.s3.key import Key
          from boto.exception import S3ResponseError
  
          import StringIO
          from . import MetadataFlo
  
          b = StringIO.StringIO()
          try:
              k = self._get_boto_key(rel_path)
              if not k:
                  return None
  
              k.get_contents_to_file(b, cb=cb, num_cb=100)
  
              b.seek(0)
  
              if return_meta:
                  d = k.metadata
                  d['size'] = k.size
                  d['etag'] = k.etag
              else:
                  d = {}
  
              return MetadataFlo(b, d)
  
          except S3ResponseError as e:
              if e.status == 404:
                  return None
              else:
                  raise e
docs: Return the object as a stream