code: def _http_headers(self):
          
          if not self.usertag:
              return {}
  
          creds = u'{}:{}'.format(
              self.usertag,
              self.password or ''
          )
          token = base64.b64encode(creds.encode())
          return {
              'Authorization': 'Basic {}'.format(token.decode())
          }
docs: Return dictionary of http headers necessary for making an http
          connection to the endpoint of this Connection.
  
          :return: Dictionary of headers