Fix list examples in python

[therve]

When a model has an example in an array, it wrongly wraps it again in a list
instead of returning the list examples. This fixes it.

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[wing328]

cc @taxpon (2017/07) @frol (2017/07) @mbohlool (2017/07) @cbornet (2017/09) @kenjones-cisco (2017/11) @tomplus (2018/10) @Jyhess (2019/01) @arun-nalla (2019/11) @spacether (2019/11)

[wing328]

LGTM

[wing328]

@therve thanks for the PR, which has been merged into master. Do we need similar fix in the python-legacy client generator? https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonLegacyClientCodegen.java#L837

[therve]

@therve thanks for the PR, which has been merged into master. Do we need similar fix in the python-legacy client generator? https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonLegacyClientCodegen.java#L837

I don't think so, because it doesn't seem to use the object example? Will try locally to make sure. Yes it needs a similar fix.

But that PR has a follow up unfortunately.