Rodent-eater in portion two Scotsmen try to divide? (6,8)

I believe the answer is:

indian mongoose

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'rodent-eater' is the definition.
I can't judge whether this defines the answer.

'in portion two scotsmen try to divide?' is the wordplay.
'two scotsmen' can mean two replacements for 'scotsman'.
'portion' becomes 'dose' (a portion of medicine).
'scotsman' becomes 'ian' (common Scottish name).
'scotsman' becomes 'mon'.
'try' becomes 'go' (both can mean an attempt).
'to divide?' means one lot of letters goes inside another (inserted letters divide the word).
'ian'+'mon'+'go'='ianmongo'
'dose' enclosing 'ianmongo' is 'dianmongoose'.
'in'+'dianmongoose'='INDIAN MONGOOSE'

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I've seen this clue in The Independent.

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