[Python] What is a with statement?

[Python] What is a with statement? Explain the usage and meaning with actual examples

With is used in the explanation of ExcelWriter, I investigated the meaning and usage, so I summarized it.

Official page (overview)Official page (example)

## Use and content of the with statement ** ■ Applications ** ** Used for processing that is a set of "start" and "end" **.

-Open the file to read and write. -Access the DB and exit after processing.

** ■ Processing content ** In the process that "start" and "end" are set If you "start" using the with statement, it will ** automatically "end" ** after the process is executed.
** ■ Merit ** -You do not have to write the termination process. -Do not forget to write the end process.
## Basic syntax of with ``` with ① Start processing as ② Variable: ③ Processing ```

① Start processing └ Describe the process to start communication such as opening a file.

② Variable └ Variable (abbreviation) for calling process ①

③ Processing └ Process to be executed. When this process is completed, the file is automatically closed (communication is disconnected).

## Code example using the with statement In the official python documentation, It is used in the open function that opens a file and ExcelWriter that opens Excel.


with open('spamspam.txt', 'w', opener=opener) as f:
    print('This will be written to somedir/spamspam.txt', file=f)

Built-in function open


with ExcelWriter('path_to_file.xlsx') as writer:

Official page of ExcelWriter

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