Even crass VIPs politely request a reply (4)

I believe the answer is:

rsvp

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'politely request a reply' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'even crass vips' is the wordplay.
'even' means one should take alternating letters (even-numbered letters are used).
'crass'+'vips'='crassvips'
The alternating letters of 'crassvips' are 'RSVP'.

Can you help me to learn more?

(Other definitions for rsvp that I've seen before include "Please reply to the French, in short" , "Please reply (abbrev.)" , "'Please reply, initially (4)'" , "Invitation abbreviation" , "Notation meaning answer the invitation" .)

I've seen this clue in the Sydney Morning Herald.

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