code: def main():
      fromYear = 2000
      toYear = 2012
  
      try:
          # MERVAL config.
          symbolsFile = os.path.join("..", "symbols", "merval.xml")
          missingDataVerifierClass = MervalMissingDataVerifier
  
          stockCallback = lambda stock: process_symbol(
              stock.getTicker(),
              fromYear,
              toYear,
              missingDataVerifierClass,
          )
          indexCallback = stockCallback
          symbolsxml.parse(symbolsFile, stockCallback, indexCallback)
      except Exception as e:
          logger.error(str(e))
  
imports: import sys
  import os
  import datetime
  import symbolsxml
  import merval_calendar
  import pyalgotrade.logger
  from pyalgotrade.barfeed import yahoofeed
label_desc: Use image node_id 3 for calling a global function with example usage: main() without return types