code: def load(self, session_id=None):
          
  
          if session_id is None:
              cookie_name = self._config.cookie_name
              self._data["session_id"] = web.cookies().get(cookie_name)
              self._data["cookieless"] = False
          else:
              if session_id == '':
                  self._data["session_id"] = None  # will be created
              else:
                  self._data["session_id"] = session_id
              self._data["cookieless"] = True
  
          # protection against session_id tampering
          if self._data["session_id"] and not self._valid_session_id(self._data["session_id"]):
              self._data["session_id"] = None
  
          self._check_expiry()
          if self._data["session_id"]:
              d = self.store[self._data["session_id"]]
              self.update(d)
              self._validate_ip()
  
          if not self._data["session_id"]:
              self._data["session_id"] = self._generate_session_id()
  
              if self._initializer:
                  if isinstance(self._initializer, dict):
                      self.update(deepcopy(self._initializer))
                  elif hasattr(self._initializer, '__call__'):
                      self._initializer()
  
          self._data["ip"] = web.ctx.ip
docs: Load the session from the store.
          session_id can be:
          - None: load from cookie
          - '': create a new cookieless session_id
          - a string which is the session_id to be used.