app\Permission::roles PHP Method

    public function roles()
    {
        return $this->belongsToMany(Role::class);
    }

 /**
  * Method for stroring a new permission in the database.
  *
  * @param PermissionRequest $request
  * @return mixed
  */
 public function store(PermissionRequest $request)
 {
     $permission = new Permission($request->all());
     $permission->save();
     if (is_null($request->get('roles'))) {
         $permission->roles()->sync([]);
     } else {
         $permission->roles()->sync($request->get('roles'));
     }
     $routes = $request->get('routes');
     foreach ($routes as $route) {
         $permission->routes()->create(['route' => $route]);
     }
     return redirect(route('rbac.permissions.index'))->withSuccess('You have successfully created a new permission.');
 }