Doesn't have the fare to take the express south (5)

I believe the answer is:

fasts

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'doesn't have the fare to take' is the definition.
I can't tell whether this defines the answer.

'express south' is the wordplay.
'express' becomes 'fast' (I've seen this in another clue).
'south' becomes 's' (abbreviation).
'fast'+'s'='FASTS'

'the' is the link.

Can you help me to learn more?

(Other definitions for fasts that I've seen before include "Abstains from food" , "Goes hungry" , "Times of abstinence" , "Avoids food" , "Goes without food" .)

I've seen this clue in the Evening Standard.

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