项目场景：

Python Flask框架编程，编写GET函数返回值

问题描述：

报错 int object is not callable

Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/flask/app.py", line 1966, in make_response
    rv = self.response_class.force_type(rv, request.environ)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/werkzeug/wrappers/base_response.py", line 269, in force_type
    response = BaseResponse(*_run_wsgi_app(response, environ))
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/werkzeug/wrappers/base_response.py", line 26, in _run_wsgi_app
    return _run_wsgi_app(*args)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/werkzeug/test.py", line 1119, in run_wsgi_app
    app_rv = app(environ, start_response)
TypeError: int object is not callable

原因分析：

Flask框架的return返回值不允许是int类型。

允许的类型有【普通字符串】【JSON数据】【元祖】