code: def get_request_headers(self, *args, **kwds):
          
          if self.request_headers:
              return self._unpack_headers(self.request_headers)
docs: A convenience method for obtaining the headers that were sent to the
          S3 server.
  
          The AWS S3 API depends upon setting headers. This method is provided as
          a convenience for debugging issues with the S3 communications.