How to create new project with Master branch use Gitlab API?

I want to create new project use Gitlab API .

Step 1

POST /api/v3/projects 
{
    "name": "api-create-test-01",
    "namespace_id": "743",
    "visibility": "private"
}

create an empty project (project id = 2794) , without branch . continue call api to initial a master branch .

Step N

try to create new file to init master:

**POST /api/v3/projects/2794/repository/files**
{
    "branch_name": "master",
    "file_path": "README.md",
    "commit_message": "initial push",
    "content": " "
}

tell me :“message”: “You are not allowed to push into this branch” :joy:

try to make a commit:

**POST /api/v3/projects/2794/repository/commits**
{
    "branch_name": "master",
    "commit_message": "initial push",
    "actions": [
    	{
    		"actions": "create",
    		 "file_path": "readme.md"
    	}
    	]
}

tell me : “message”: “You are not allowed to push into this branch” :sweat_smile::sob:

How can I create new project with Master branch only use Gitlab API?

I have resolved this problem Finally.

POST http://GITLAB_SERVER/api/v3/projects
{
“name”: “api-create-test”,
“namespace_id”: “743”,
“visibility”: “private”,
"import_url": "http://GITLAB_SERVER/root/template.git"
}

use import_url i can create an empty project whith master branch , without any clone .
PS: the template.git initialize at the beginning.