Add __repr__ for DagTag so it displays properly in /dagmodel/show

[XD-DENG]

Currently Dag Tags are not displayed properly in UI page /dagmodel/show/<dag_id>

This issue exists in both master and 1.10.10

How to Reproduce

Before Fix

After fix

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[kaxil]

can we add a simple test for this?

[XD-DENG]

can we add a simple test for this?

Thanks @kaxil . I was thinking of this as well, but didn't do it given it's too simple change.

Let me re-think how I should do it. Will update here.

[kaxil]

can we add a simple test for this?

Thanks @kaxil . I was thinking of this as well, but didn't do it given it's too simple change.

Let me re-think how I should do it. Will update here.

I mean just assert that "repr(ExampleDagTag) == 'ExampleDagTag'"

[XD-DENG]

Hi @kaxil , unit test is updated. May be a bit "more" than you expected, but I think it's worthwhile

[kaxil]

Nice, I like it