Reformers sit around surrounded by maps (9)

I believe the answer is:

chartists

'reformers' is the definition.
(Chartist is an example)

'sit around surrounded by maps' is the wordplay.
'around' is an anagram indicator.
'surrounded by' indicates putting letters inside.
'maps' becomes 'charts' (chart is a kind of map).
'sit' anagrammed gives 'ist'.
'ist' going inside 'charts' is 'CHARTISTS'.

I've seen this clue in The Telegraph.

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