When i start mongo db on macOS console by run command mongod, i got below error message. {“t”:{“$date”:”2020-09-09T10:45:30.049+08:00″},”s”:”E”,  “c”:”NETWORK”,  “id”:23024,   “ctx”:”initandlisten”,”msg”:”Failed to unlink socket file”,”attr”:{“path”:”/tmp/mongodb-27017.sock”,”error”:”Permission denied”}}

After you write down your Jupyter notebook file content, if you want to show the Jupyter notebook content to others like a PPT, you can read this article. This article will tell you how to convert a Jupyter notebook file to a PPT-style presentation Html file.

When you run print(‘ hello python ‘) in python code, it always print the text on screen, this is because python standard output is screen console. But we always want to print the text to a file instead of screen console, especially print exception error messages when exception occurred in python source code.

When I execute a system program using the python subprocess module’s run method in windows, I meet an error message like below.