A long time to muse (5)

I believe the answer is:

erato

'muse' is the definition.
(I know that Erato is a muse)

'a long time to' is the wordplay.
'a long time' becomes 'era' (a long period of time).
'era'+'to'='ERATO'

(Other definitions for erato that I've seen before include "Greek muse - orate (anag)" , "Source of poetic inspiration" , "One of the Muses" , "Inspiring female" , "Poetic Muse ; eighteen (anag.)" .)

I've seen this clue in The Globe and Mail and The Telegraph.

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