Tramp around one town in Nigeria (4)

I believe the answer is:

mubi

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

'tramp around one' is the wordplay.
'tramp' becomes 'bum' (synonyms).
'around' says the letters should be written backwards.
'one' becomes 'i' (Roman numeral).
'bum' backwards is 'mub'.
'mub'+'i'='MUBI'

Can you help me to learn more?

I've seen this clue in The Hindu.

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