// First find the import spec.
	var importSpec *ast.ImportSpec
	walk(f, func(n any) {
		if importSpec != nil {
			return
		}
		spec, ok := n.(*ast.ImportSpec)
		if !ok {
			return
		}
		path, err := strconv.Unquote(spec.Path.Value)
		if err != nil {
			return
		}
		if path == "golang.org/x/tools/go/exact" {
			importSpec = spec
		}

	})
	if importSpec == nil {
		return false
	}

func Imports(fset *token.FileSet, f *ast.File) [][]*ast.ImportSpec {
	var groups [][]*ast.ImportSpec

	for _, decl := range f.Decls {
		genDecl, ok := decl.(*ast.GenDecl)
		if !ok || genDecl.Tok != token.IMPORT {
			break
		}

		group := []*ast.ImportSpec{}

		var lastLine int
		for _, spec := range genDecl.Specs {
			importSpec := spec.(*ast.ImportSpec)
			pos := importSpec.Path.ValuePos
			line := fset.Position(pos).Line

}

func importPath(s Spec) string {
	t, err := strconv.Unquote(s.(*ImportSpec).Path.Value)
	if err == nil {
		return t
	}
	return ""
}

func importName(s Spec) string {
	n := s.(*ImportSpec).Name
	if n == nil {
		return ""
	}
	return n.Name
}

func importComment(s Spec) string {
	c := s.(*ImportSpec).Comment
	if c == nil {
		return ""
	}
	return c.Text()
}

		}
	}
	after(x)
}

// imports reports whether f imports path.
func imports(f *ast.File, path string) bool {
	return importSpec(f, path) != nil
}

// importSpec returns the import spec if f imports path,
// or nil otherwise.
func importSpec(f *ast.File, path string) *ast.ImportSpec {
	for _, s := range f.Imports {
		if importPath(s) == path {
			return s
		}
	}
	return nil
}

var res = map[string]string{
	" 5: *ast.File":       "the very first comment\npackage p\n",
	" 5: *ast.Ident":      " the name is p\n",
	" 8: *ast.GenDecl":    "imports\n",
	" 9: *ast.ImportSpec": "bytes\n",
	"10: *ast.ImportSpec": "fmt\n",
	"16: *ast.GenDecl":    "T\nalso associated with T\n",
	"17: *ast.Field":      "associated with a, b, c\n",
	"19: *ast.Field":      "associated with x, y\nfloat values\n",

func findImportGroupStarts(imps []*ast.ImportSpec) []token.Pos {
	startImps := findImportGroupStarts1(imps)
	groupStarts := make([]token.Pos, len(startImps))
	for i, imp := range startImps {
		groupStarts[i] = imp.Pos()
	}
	return groupStarts
}

// Helper for findImportGroupStarts to ease testing.
func findImportGroupStarts1(origImps []*ast.ImportSpec) []*ast.ImportSpec {
	// Copy to avoid mutation.

	sawC := false
	for _, decl := range ast1.Decls {
		switch decl := decl.(type) {
		case *ast.GenDecl:
			for _, spec := range decl.Specs {
				s, ok := spec.(*ast.ImportSpec)
				if !ok || s.Path.Value != `"C"` {
					continue
				}
				sawC = true
				if s.Name != nil {
					error_(s.Path.Pos(), `cannot rename import "C"`)
				}
				cg := s.Doc

// constant, type, or variable declaration.
type (
	// The Spec type stands for any of *ImportSpec, *ValueSpec, and *TypeSpec.
	Spec interface {
		Node
		specNode()
	}

	// An ImportSpec node represents a single package import.
	ImportSpec struct {
		Doc     *CommentGroup // associated documentation; or nil
		Name    *Ident        // local package name (including "."); or nil

pkg go/types, method (*Alias) String() string #63223
pkg go/types, method (*Alias) Underlying() Type #63223
pkg go/types, method (*Info) PkgNameOf(*ast.ImportSpec) *PkgName #62037
pkg go/types, method (Checker) PkgNameOf(*ast.ImportSpec) *PkgName #62037
pkg go/types, type Alias struct #63223
pkg go/types, type Info struct, FileVersions map[*ast.File]string #62605
pkg go/version, func Compare(string, string) int #62039

	case *ast.Ident:
		children = append(children,
			tok(n.NamePos, len(n.Name)))

	case *ast.IfStmt:
		children = append(children,
			tok(n.If, len("if")))

	case *ast.ImportSpec:
		// TODO(adonovan): ImportSpec.{Doc,EndPos}?

	case *ast.IncDecStmt:
		children = append(children,
			tok(n.TokPos, len(n.Tok.String())))

	case *ast.IndexExpr:
		children = append(children,