ENH: Support mangle_dupe_cols=False in pd.read_csv()

[gfyoung]

#12935 added full support for duplicate column names (in header or in names) by mangling them. While this has been considered acceptable by users, ideally, we would like to not have to mangle them.

[gfyoung]

@jreback : Given what you said in #17060, is this something we should still pursue ?

[jorisvandenbossche]

Depending on how difficult this is, I would personally still have it as our goal to have mangle_dupe_cols=False implemented some time.

[caniko]

What is the ETA on this issue?

[jreback]

when / if a community pull request happens

[gfyoung]

@caniko2 : This is quite a tricky one given that duplicate column names have unusual behavior in pandas. You are more than welcome to submit a PR to implement it if you like.