When it is required to close a file in Python?

Question

Say I have the following code:

remote = urlopen('www...../file.txt')
with open(file='file', mode='wb') as local:
    local.write(remote.read())

Do I need to also do:

local.close()
remote.close()

How do I know when close() is needed and when Python takes care of it for me?

when you open the file using `with`, python takes care of it. — Sociopath, Apr 10 '19 at 09:55
This might be helpful: https://stackoverflow.com/questions/17459867/file-open-and-close-in-python — ConsistentProgrammer, Apr 10 '19 at 09:55
@Luis: I only wanted to share information regarding file open/close — ConsistentProgrammer, Apr 10 '19 at 09:58
@Luis Use `with` for that as well, and it will be done automatically. — Barmar, Apr 10 '19 at 09:58
You can have multiple `with` on the same line. `with urlopen(...) as remote, open(...) as local:` — Barmar, Apr 10 '19 at 11:09

score 3 · Accepted Answer · answered Apr 10 '19 at 09:58

If you use a context manager ( which is what the "with.." statement is) then you don't need to use the .close.

Python manages the resources for you in this case. This is a good article that goes into the detail of how it works.

Its good practice to use context managers whenever possible, and you can create your own using the contextlib library.

score 1 · Answer 2 · answered Apr 10 '19 at 10:00

1

You do not have to close the file explicitly when you are using python with statement. So you are good with local object. And this post explains why you should close the remote resource explicitly.

answered Apr 10 '19 at 10:00

Kusal Hettiarachchi

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When it is required to close a file in Python?

2 Answers2