Title song of John Lennon's second solo album (7)

I believe the answer is:

imagine

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'title song' is the definition.
'imagine' can be an answer for 'song' (song by John Lennon). I am not certain of the 'title' bit.

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for imagine that I've seen before include "1971 John Lennon song" , "Assume" , "Picture to oneself" , "Conjure up in mind, visualise" , "Fancy - Lennon song" .)

I've seen this clue in The Times.

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