### Tutorial for model upload
1. Size of zip files should not exceeds 5MB;
2. Only 3D models in the obj format are supported；
3. Only zip format supported；
4. The package file needs to contain three files: textures, models, and mtl files;
5. The packaged file must not contain folders. All files, such as maps, models, and mtl files, should be placed in the root directory, as shown below:
