Crossword Genius

In patches, perhaps, they were cool swingers (7)

Ross

I believe the answer is:

hepcats

I'm a little stuck... Click here to teach me more about this clue!

'they were cool swingers' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'in patches' is the wordplay.
'patches' can be anagrammed to 'HEPCATS'.
However, I am not clear how this is indicated.

'perhaps' is the link.

Can you help me to learn more?

(Another definition for hepcats that I've seen is " Trendies".)

I've seen this clue in the Evening Standard.
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