Popular party tourist regularly within building (7)

I believe the answer is:

indoors

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'popular party tourist regularly within building' is the definition.
I can't judge whether this defines the answer.

'popular party tourist regularly' is the wordplay.
'popular' becomes 'in' ('in' can mean trendy).
'party' becomes 'do' (do can informally mean a party).
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
The alternate letters of 'tourist' are 'ors'.
'in'+'do'+'ors'='INDOORS'

Can you help me to learn more?

(Other definitions for indoors that I've seen before include "Within house" , "With a roof over one's head?" , "Covered" , "Within a building" , "under cover" .)

I've seen this clue in The Times.

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