He's sunny, but not Jim (3)

I believe the answer is:

ray

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'he's' is the definition.

I cannot understand how the remainder of the clue works.

(Other definitions for ray that I've seen before include "Beam; flat-bodied fish" , "Gleam" , "bit of sunshine" , "A bright beam or flat fish" , "Narrow beam of light" .)

I've seen this clue in the Evening Standard.

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