It is kept from going astray by crooks (5,2,5)

I believe the answer is:

flock of sheep

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

'it is kept from' is the wordplay.
I cannot really see how this works, but
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is found in the answer.
'from' could be 'of' (of can mean from or belonging to) and 'of' is located in the answer.
This explanation may well be incorrect...

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

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