[AIRFLOW-4828] Remove parameter python_version

[zhongjiajie]

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Jira

• My PR addresses the following Airflow Jira issues and references them in the PR title. For example, "[AIRFLOW-XXX] My Airflow PR"
  • https://issues.apache.org/jira/browse/AIRFLOW-4828

Description

• Here are some details about my PR, including screenshots of any UI changes:

Part of AIP-3 Drop support for Python 2

Code Quality

• Passes flake8

[OmerJog]

Shouldnt you target https://issues.apache.org/jira/browse/AIRFLOW-4828 ?

[zhongjiajie]

@OmerJog Oh, my bad. Thanks for you help

[kurtqq]

I don't think we should remove python_version parameter.
If I run Airflow on Python 3.5 and want to run a task with Python 3.7 I need the python_version parameter.
Moreover in the future Python 4 will be released. Airflow will likely support both for a while....

I think the python_version needs to stay it's not unique to Python 2.7

I also think that if someone wants to run something with Python 2.7 with the PythonVirtualenvOperator he is more than welcome. There is no need to prevent the user from doing so. Airflow can just remove the test for this so if something is not working it's the user problem.

[XD-DENG]

Agree with @kurtqq .

• To my understanding, [AIP-3 drop support Python 2] is to drop Py2 support to Airflow itself only.
• Minor version ("x" in "3.x") matters.

[zhongjiajie]

Will close it, thanks for the clarification @kurtqq @XD-DENG

[XD-DENG]

Thanks @zhongjiajie