return false, err
	}
	requirements = rs
	return changed, err
}

// OverrideRoots edits the global requirement roots by replacing the specific module versions.
func OverrideRoots(ctx context.Context, replace []module.Version) {
	requirements = overrideRoots(ctx, requirements, replace)
}

func overrideRoots(ctx context.Context, rs *Requirements, replace []module.Version) *Requirements {
	drop := make(map[string]bool)

			v := gover.Local()
			if opts != nil && opts.TidyGoVersion != "" {
				v = opts.TidyGoVersion
			}
			addGoStmt(MainModules.ModFile(mainModule), mainModule, v)
			rs = overrideRoots(ctx, rs, []module.Version{{Path: "go", Version: v}})

			// We need to add a 'go' version to the go.mod file, but we must assume
			// that its existing contents match something between Go 1.11 and 1.16.

				// pruning and semantics all along, but there may have been — and may
				// still be — requirements on higher versions in the graph.
				tidy := overrideRoots(ctx, rs, []module.Version{{Path: "go", Version: ld.TidyGoVersion}})
				mg, err := tidy.Graph(ctx)
				if err != nil {
					ld.error(err)
				}
				if v := mg.Selected("go"); v == ld.TidyGoVersion {