[Haskell-beginners] How to use Text.Printf w/ custom types

[Baa]

Hello All!

As I understand to use Text.Printf.printf with custom types or to
return result as Text instead of String I must implement some
class instances: PrintfType, PrintfArg. But how to do this if they are
exported from module as type-names only - without its methods (i.e. not
"Printf (..)", but "Printf") ?

I tried to import Text.Printf.Internal but seems that no such
submodule...

Any ideas?

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Best regards, Paul