code: def execute_from_command_line(argv=None):
      
      if not argv:
          argv = sys.argv
  
      # prog_name = argv[0]
      system_commands = find_commands(system_command_dir())
      project_commands = find_commands(project_command_dir())
  
      project_package = project_package_name()
  
      command = argv[1] if len(argv) > 1 else None
  
      # Are we running a core command?
      if command in system_commands:
          cmd = load_command_class('demosys', command)
          cmd.run_from_argv(argv)
      elif command in project_commands:
          cmd = load_command_class(project_package, command)
          cmd.run_from_argv(argv)
      else:
          print("Available commands:")
          for name in system_commands:
              print(" - {}".format(name))
          for name in project_commands:
              print(" - {}".format(name))
docs: Currently the only entrypoint (manage.py, demosys-admin)