code: def testBuyAndSellBreakEvenWithCommision(self):
      posTracker = returns.PositionTracker(broker.IntegerTraits())
      posTracker.buy(1, 10, 0.5)
      self.assertEqual(posTracker.getAvgPrice(), 10)
      posTracker.sell(1, 11, 0.5)
      self.assertEqual(posTracker.getPnL(includeCommissions=False), 1)
      self.assertEqual(posTracker.getPnL(), 0)
      self.assertEqual(
          posTracker.getReturn(includeCommissions=False), 0.1
      )
      self.assertEqual(posTracker.getReturn(), 0)
  
imports: import datetime
  from .None import common
  from .None import strategy_test
  from .None import position_test
  from testcases import test_strategy
  from pyalgotrade.barfeed import yahoofeed
  from pyalgotrade.barfeed import csvfeed
  from pyalgotrade.stratanalyzer import returns
  from pyalgotrade import broker
  from pyalgotrade import marketsession
label_desc: Use image node_id 10 for calling the PosTrackerTestCase obj's underlying member method code with example usage: obj.testBuyAndSellBreakEvenWithCommision() without return types