Getting the said keys with no trouble (4)

I believe the answer is:

ease

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'no trouble' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for ease that I've seen before include "Make less severe, comfort" , "Freedom from worries" , "Freedom from pain or anxiety" , "Lack of worry or agitation" , "Facilitate; repose" .)

I've seen this clue in the Evening Standard.

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