[
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  {"type":"Text","value":" "},
  {"type":"LiteralStringAffix","value":"f"},
  {"type":"LiteralStringDouble","value":"\""},
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  {"type":"LiteralStringInterpol","value":"{"},
  {"type":"NameBuiltin","value":"len"},
  {"type":"Punctuation","value":"("},
  {"type":"NameBuiltinPseudo","value":"self"},
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]