You can upload your image to the self-building chevereto by this tool. Actually , many people use shareX on Windows system , however , if you work on the OS X , mac os and linux , It's terrible and time wasting to upload a image to self chevereto. If you have same issue , It's time to use my tool.
You should find your API Key in yourselves'chevereto , It located at setting -> API , and copy it to the upload.py.
Enjoy it !!!