How does open() work with and without `with`?

Question

I\'d like to write a function similar to open. I\'d like to be able to call it with with, but also without with.

When I use

Answer 1

Do you really need to use contextlib.contextmanager? If you have a custom stream you would want to use Poke's solution.

But since you are just returning a file object, why go through all the hassle:

def versioned(file_path, mode):
    version = calculate_version(file_path, mode)
    return open(file_path, mode)


with versioned('test.conf', 'r') as stream:
   print stream.read()

f = versioned('test.conf', 'r')
print f.read()
f.close()

Both will work perfectly fine :)