docs: def faz(input_file, variables=None):
      """
      FAZ entry point.
      """
      logging.debug("input file:\n {0}\n".format(input_file))
      tasks = parse_input_file(input_file, variables=variables)
      print("Found {0} tasks.".format(len(tasks)))
      graph = DependencyGraph(tasks)
      graph.show_tasks()
      graph.execute()