The realm of the imagination? (4,2,6)

I believe the answer is:

land of dreams

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'the' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'realm of the imagination?' is the wordplay.
'realm' becomes 'land' (I've seen this in another clue).
'the imagination?' becomes 'dreams' (I am not sure about this - if you are sure you should believe this answer much more).
'land'+'of'+'dreams'='LAND OF DREAMS'

Can you help me to learn more?

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

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