Alex-related errors building with newer stackage snapshot

[RichardWarfield]

I get the following errors when trying to build with Stackage snapshot 13.29 (GHC 8.6.5). I'm not familiar with Alex so am not sure where these identifiers should be defined.

/home/richard/workspace/third-party/language-python/.stack-work/dist/x86_64-linux-tinfo6/Cabal-2.4.0.1/build/Language/Python/Version2/Parser/Lexer.hs:45:14: error:
 Not in scope: type constructor or class ‘AlexAddr’
 |
45 | alex_base :: AlexAddr
 | ^^^^^^^^

/home/richard/workspace/third-party/language-python/.stack-work/dist/x86_64-linux-tinfo6/Cabal-2.4.0.1/build/Language/Python/Version2/Parser/Lexer.hs:49:15: error:
 Not in scope: type constructor or class ‘AlexAddr’
 |
49 | alex_table :: AlexAddr
 | ^^^^^^^^

/home/richard/workspace/third-party/language-python/.stack-work/dist/x86_64-linux-tinfo6/Cabal-2.4.0.1/build/Language/Python/Version2/Parser/Lexer.hs:53:15: error:
 Not in scope: type constructor or class ‘AlexAddr’
 |
53 | alex_check :: AlexAddr
 | ^^^^^^^^

/home/richard/workspace/third-party/language-python/.stack-work/dist/x86_64-linux-tinfo6/Cabal-2.4.0.1/build/Language/Python/Version2/Parser/Lexer.hs:57:15: error:
 Not in scope: type constructor or class ‘AlexAddr’
 |
57 | alex_deflt :: AlexAddr
 | ^^^^^^^^

/home/richard/workspace/third-party/language-python/src/Language/Python/Version2/Parser/Lexer.x:226:5: error:
 Not in scope: data constructor ‘AlexEOF’
 |
226 | AlexEOF -> do
 | ^^^^^^^

/home/richard/workspace/third-party/language-python/src/Language/Python/Version2/Parser/Lexer.x:244:5: error:
 Not in scope: data constructor ‘AlexError’
 |
244 | AlexError _ -> lexicalError
 | ^^^^^^^^^

/home/richard/workspace/third-party/language-python/src/Language/Python/Version2/Parser/Lexer.x:245:5: error:
 Not in scope: data constructor ‘AlexSkip’
 |
245 | AlexSkip (nextLocation, _bytes, rest) len -> do
 | ^^^^^^^^

/home/richard/workspace/third-party/language-python/src/Language/Python/Version2/Parser/Lexer.x:249:5: error:
 Not in scope: data constructor ‘AlexToken’
 Perhaps you meant variable ‘lexToken’ (line 221)
 |
249 | AlexToken (nextLocation, _bytes, rest) len action -> do
 | ^^^^^^^^^

stack exec -- alex --version gives Alex version 3.2.4, (c) 2003 Chris Dornan and Simon Marlow

[MarisaKirisame]

Is there any update? I want to use this package.