Dropping Ecstasy, ease the undies off in Paris suburbs (5-2-5)

I believe the answer is:

hauts-de-seine

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'dropping ecstasy ease the undies off in paris suburbs' is the definition.
I can't judge whether this defines the answer.

'dropping ecstasy ease the undies off' is the wordplay.
'dropping' indicates named letters should be taken away (some letters drop out).
'ecstasy' becomes 'E' (informal term for the drug).
'off' indicates anagramming the letters.
'ease'+'the'+'undies'='easetheundies'
'easetheundies' with 'e' removed is 'asetheundies'.
'asetheundies' is an anagram of 'HAUTS-DE-SEINE'.

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I've seen this clue in The Guardian.

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