Brussels frolic: is one involved? (4,2)

I believe the answer is:

euro mp

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'one involved?' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'brussels frolic' is the wordplay.
'brussels' becomes 'EU' (European Parliament is based in Brussels).
'frolic' becomes 'romp' (synonyms).
'eu'+'romp'='EURO-MP'

'is' is the link.

Can you help me to learn more?

(Other definitions for euro mp that I've seen before include "Political representative" , "Politician" .)

I've seen this clue in The Times.

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