code: def __init__(self, dbFilePath, frequency, maxLen=None):
      super(Feed, self).__init__(frequency, maxLen)
  
      self.__db = Database(dbFilePath)
  
imports: from pyalgotrade.barfeed import dbfeed
  from pyalgotrade.barfeed import membf
  from pyalgotrade import bar
  from pyalgotrade.utils import dt
  import sqlite3
  import os
label_desc: Use image node_id 1 to create a new Feed object from inherited base classes: membf with example: obj = Feed(dbFilePath, frequency, maxLen)