Traceback (most recent call last):

  File "C:\Program Files\JetBrains\PyCharm 2018.1.2\helpers\pydev\pydevd.py", line 1664, in <module>

    main()

  File "C:\Program Files\JetBrains\PyCharm 2018.1.2\helpers\pydev\pydevd.py", line 1658, in main

    globals = debugger.run(setup['file'], None, None, is_module)

  File "C:\Program Files\JetBrains\PyCharm 2018.1.2\helpers\pydev\pydevd.py", line 1085, in run

    runpy._run_module_as_main(module_name, alter_argv=False)

  File "c:\program files\python36_64\Lib\runpy.py", line 193, in _run_module_as_main

    "__main__", mod_spec)

  File "c:\program files\python36_64\Lib\runpy.py", line 85, in _run_code

    exec(code, run_globals)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask\__main__.py", line 14, in <module>

    main(as_module=True)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask\cli.py", line 894, in main

    cli.main(args=args, prog_name=name)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask\cli.py", line 557, in main

    return super(FlaskGroup, self).main(*args, **kwargs)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\click\core.py", line 697, in main

    rv = self.invoke(ctx)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\click\core.py", line 1066, in invoke

    return _process_result(sub_ctx.command.invoke(sub_ctx))

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\click\core.py", line 895, in invoke

    return ctx.invoke(self.callback, **ctx.params)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\click\core.py", line 535, in invoke

    return callback(*args, **kwargs)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\click\decorators.py", line 64, in new_func

    return ctx.invoke(f, obj, *args[1:], **kwargs)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\click\core.py", line 535, in invoke

    return callback(*args, **kwargs)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask\cli.py", line 767, in run_command

    app = DispatchingApp(info.load_app, use_eager_loading=eager_loading)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask\cli.py", line 293, in __init__

    self._load_unlocked()

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask\cli.py", line 317, in _load_unlocked

    self._app = rv = self.loader()

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask\cli.py", line 372, in load_app

    app = locate_app(self, import_name, name)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask\cli.py", line 235, in locate_app

    __import__(module_name)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\RestfulAPI\restful_app.py", line 4, in <module>

    app = create_app()

  File "C:\Users\zhaow\Documents\WorkSpace\Python\RestfulAPI\app\app.py", line 26, in create_app

    register_plugin(app)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\RestfulAPI\app\app.py", line 17, in register_plugin

    db.create_all(app)

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask_sqlalchemy\__init__.py", line 963, in create_all

    self._execute_for_all_tables(app, bind, 'create_all')

  File "C:\Users\zhaow\Documents\WorkSpace\Python\venv\lib\site-packages\flask_sqlalchemy\__init__.py", line 949, in _execute_for_all_tables

    for bind in binds:

TypeError: 'Flask' object is not iterable