[SPARK-23698] Remove raw_input() from Python 2

[cclauss]

Signed-off-by: cclauss [email protected]

What changes were proposed in this pull request?

Humans will be able to enter text in Python 3 prompts which they can not do today.
The Python builtin raw_input() was removed in Python 3 in favor of input(). This PR does the same thing in Python 2.

How was this patch tested?

(Please explain how this patch was tested. E.g. unit tests, integration tests, manual tests)
(If this patch involves UI changes, please attach a screenshot; otherwise, remove this)
flake8 testing

Please review http://spark.apache.org/contributing.html before opening a pull request.

[HyukjinKwon]

If we can do the opposite, the diff should be only 4 lines though

[cclauss]

Two downsides to that approach:

1. We stick with the legacy Python syntax which will unnecessarily complicate our lives (and our diffs) in 18 months
2. This approach reduces the linting errors from 10 down to just 2.

[HyukjinKwon]

Are you actually able to roughly check if those scripts can be ran against Python 3?

[cclauss]

Tested data entry...
In ./dev/merge_spark_pr.py just after clean_up(), I added the lines:

while not continue_maybe('y to conntinue'):
    print('loop')
sys.exit()

Test: 'y' or 'Y' caused a loop while all others including "", "yes", "n", "N", "0", "1", "." caused an exit()
Identical results on both Python 2 and Python 3

---

In ./dev/create-release/releaseutils.py just after _yesOrNoPrompt() I added the lines:

while not yesOrNoPrompt('y to quit'):
    print('got an 'n'')
sys.exit()

Test: 'y' caused an exit() while all others including "", "Y", "yes", "n", "N", "0", "1", "." caused a loop
Identical results on both Python 2 and Python 3

[HyukjinKwon]

ok to test

[HyukjinKwon]

LGTM

[SparkQA]

Test build #92570 has finished for PR 21702 at commit 960769a.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[HyukjinKwon]

Merged to master