code: def set(self, key, value=None, dir=False, refresh=False, ttl=None,
              prev_value=None, prev_index=None, prev_exist=None, timeout=None):
          
          url = self.make_key_url(key)
          data = self.build_args({
              'value': (six.text_type, value),
              'dir': (bool, dir or None),
              'refresh': (bool, refresh or None),
              'ttl': (int, ttl),
              'prevValue': (six.text_type, prev_value),
              'prevIndex': (int, prev_index),
              'prevExist': (bool, prev_exist),
          })
          try:
              res = self.session.put(url, data=data, timeout=timeout)
          except:
              self.erred()
          return self.wrap_response(res)
docs: Requests to create an ordered node into a node by the given key.