old_contents: import logging
  
  log = logging.getLogger(__name__)
  
  
  def migrate_db(conf, start, end):
      current = start
      while current < end:
          if current == 1:
              from .migrate1to2 import do_migration
          elif current == 2:
              from .migrate2to3 import do_migration
          elif current == 3:
              from .migrate3to4 import do_migration
          elif current == 4:
              from .migrate4to5 import do_migration
          elif current == 5:
              from .migrate5to6 import do_migration
          elif current == 6:
              from .migrate6to7 import do_migration
          elif current == 7:
              from .migrate7to8 import do_migration
          elif current == 8:
              from .migrate8to9 import do_migration
          else:
              raise Exception("DB migration of version {} to {} is not available".format(current,
                                                                                         current+1))
          do_migration(conf)
          current += 1
          log.info("successfully migrated the database from revision %i to %i", current - 1, current)
      return None
  
  
  def run_migration_script():
      import sys
      log_format = "(%(asctime)s)[%(filename)s:%(lineno)s] %(funcName)s(): %(message)s"
      logging.basicConfig(level=logging.DEBUG, format=log_format, filename="migrator.log")
      sys.stdout = open("migrator.out.log", 'w')
      sys.stderr = open("migrator.err.log", 'w')
      migrate_db(sys.argv[1], int(sys.argv[2]), int(sys.argv[3]))
  
  
  if __name__ == "__main__":
      run_migration_script()
  
new_contents: import logging
  
  log = logging.getLogger(__name__)
  
  
  def migrate_db(conf, start, end):
      current = start
      while current < end:
          if current == 1:
              from .migrate1to2 import do_migration
          elif current == 2:
              from .migrate2to3 import do_migration
          elif current == 3:
              from .migrate3to4 import do_migration
          elif current == 4:
              from .migrate4to5 import do_migration
          elif current == 5:
              from .migrate5to6 import do_migration
          elif current == 6:
              from .migrate6to7 import do_migration
          elif current == 7:
              from .migrate7to8 import do_migration
          elif current == 8:
              from .migrate8to9 import do_migration
          elif current == 9:
              from .migrate9to10 import do_migration
          else:
              raise Exception("DB migration of version {} to {} is not available".format(current,
                                                                                         current+1))
          do_migration(conf)
          current += 1
          log.info("successfully migrated the database from revision %i to %i", current - 1, current)
      return None
  
  
  def run_migration_script():
      import sys
      log_format = "(%(asctime)s)[%(filename)s:%(lineno)s] %(funcName)s(): %(message)s"
      logging.basicConfig(level=logging.DEBUG, format=log_format, filename="migrator.log")
      sys.stdout = open("migrator.out.log", 'w')
      sys.stderr = open("migrator.err.log", 'w')
      migrate_db(sys.argv[1], int(sys.argv[2]), int(sys.argv[3]))
  
  
  if __name__ == "__main__":
      run_migration_script()
  
subject: add missing migrator line