[Python] Fix #10948 wrong mode opened file fixed

[goDeni]

PR checklist

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Description of the PR

(details of the change, additional tests that have been done, reference to the issue for tracking, etc)

[goDeni]

@kenjones-cisco please review this PR

[goDeni]

I'm tired of doing dirty hacks for these methods to work
Community need this mini-fix

[HugoMario]

Hello @goDeni,

Thanks for catching this issue and file a PR, however i think we should not replace the wb modes without leaving an option to the others 36 developers that worked on this and considered it as a valid option.

So, my propose is, add an option to the generator, and when this option is present use the w mode instead of wb. wdyt?

[goDeni]

Hello @goDeni,

Thanks for catching this issue and file a PR, however i think we should not replace the wb modes without leaving an option to the others 36 developers that worked on this and considered it as a valid option.

So, my propose is, add an option to the generator, and when this option is present use the w mode instead of wb. wdyt?

Option to the generator is solve problem, but this take out implementation details

There is only one case when this method is called
is called when response_type='file' and _preload_content=True

and response.data always has str type

swagger-codegen/modules/swagger-codegen/src/main/resources/python/rest.mustache

Line 213 in 068b1eb

r.data = r.data.decode('utf8')

i don't see case when this method work correctly

if you can show me this case, i'll glad