A sign concealed in a ghetto (3,4)

I believe the answer is:

the goat

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'a sign' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.

'concealed in a ghetto' is the wordplay.
'concealed in' indicates an anagram.
'a'+'ghetto'='aghetto'
'aghetto' is an anagram of 'THE GOAT'.

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I've seen this clue in The Daily Express.

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