Useful animal left to a holy man (5)

I believe the answer is:

llama

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'useful animal' is the definition.
'llama' can be an answer for 'animal' (I've seen this before). I am unsure of the 'useful' bit.

'left to a holy man' is the wordplay.
'left' becomes 'l' (common abbreviation).
'to a holy man' becomes 'lama' (I've seen this in another clue).
'l'+'lama'='LLAMA'

Can you help me to learn more?

(Other definitions for llama that I've seen before include "Peruvian transportation" , "As bearer of burdens" , "South American native" , "Alpaca-like animal" , "South-American cud-chewing animal" .)

I've seen this clue in the Evening Standard.

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