Tony upset about haul that's worthless (7)

I believe the answer is:

toytown

'worthless' is the definition.
(toytown can mean unserious or silly)

'tony upset about haul' is the wordplay.
'upset' indicates anagramming the letters.
'about' means one lot of letters goes inside another.
'haul' becomes 'tow' (tow is a kind of haul).
'tony' is an anagram of 'toyn'.
'toyn' placed around 'tow' is 'TOYTOWN'.

'that's' is the link.

(Another definition for toytown that I've seen is " Larry the Lamb's home".)

I've seen this clue in The Guardian.

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