code: def createDataSeries(self, key, maxLen):
      return dataseries.SequenceDataSeries(maxLen)
  
file_path: pyalgotrade/pyalgotrade/feed/memfeed.py
imports: from pyalgotrade import feed
  from pyalgotrade import dataseries
label_desc: Use image node_id 8 for calling the MemFeed obj's underlying member method code with example usage: obj.createDataSeries(key, maxLen) and returns: dataseries