---input--- message.append(f' [line {lineno:2d}]') ---tokens--- 'message' Name '.' Operator 'append' Name '(' Punctuation 'f' Literal.String.Affix "'" Literal.String.Single ' [line ' Literal.String.Single '{' Literal.String.Interpol 'lineno' Name ':' Literal.String.Interpol '2d' Literal.String.Single '}' Literal.String.Interpol ']' Literal.String.Single "'" Literal.String.Single ')' Punctuation '\n' Text.Whitespace