code: def onStart(self):
      self.onStartCalled = True
  
imports: import datetime
  from .None import common
  from pyalgotrade import strategy
  from pyalgotrade import broker
  from pyalgotrade.barfeed import yahoofeed
label_desc: Use image node_id 4 for calling the TestStrategy obj's underlying member method code with example usage: obj.onStart() without return types