What might raise temperature at garden party? Chatter and spirit! (3,6)

I believe the answer is:

gas bottle

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'what might raise temperature at garden party?' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'chatter and spirit' is the wordplay.
'chatter' becomes 'gas' (I've seen this in another clue).
'and' is a charade indicator (letters next to each other).
'spirit' becomes 'bottle' (I have seen 'The spirit' mean 'bottle' so perhaps 'spirit' could also mean 'bottle').
'gas'+'bottle'='GAS-BOTTLE'

Can you help me to learn more?

I've seen this clue in The Independent.

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