YAML: It's Time to Move On(nestedtext.org)

    name: Install dependencies
    run:
        > python -m pip install --upgrade pip
        > pip install pytest
        > if [ -f 'requirements.txt' ]; then pip install -r requirements.txt; fi

    [Install Dependencies]
    run=/path/to/install-script

  ( cat << EOF
  # yes, comments are allowed
  name: "Python package"
  on: "push"
  build {
    python_version: ["3.6", "3.7", "3.8", "3.9", "3.10"]
    steps: [
      {
        name: "Install dependencies"
          run:
            "python -m pip install --upgrade pip\n"
            "pip install pytest\n"
            "if [ -f 'requirements.txt' ]; then pip install -r requirements.txt; fi\n"
      },
      {
        name: "Test with pytest"
        run: "pytest\n"
      }
    ]
  }
  EOF
  ) | protoc --encode=Config config.proto  | protoc --decode=Config config.proto
  
  name: "Python package"
  on: "push"
  build {
    python_version: "3.6"
    python_version: "3.7"
    python_version: "3.8"
    python_version: "3.9"
    python_version: "3.10"
    steps {
      name: "Install dependencies"
      run: "python -m pip install --upgrade pip\npip install pytest\nif [ -f \'requirements.txt\' ]; then pip   install -r requirements.txt; fi\n"
    }
    steps {
      name: "Test with pytest"
      run: "pytest\n"
    }
  }

    {
      "name": "my-tool",
      "#comment-1": "Don’t change the version!",
      "version": "42.1337.0"
    }

   [1,2,3]

   [1,2,3,4]

   - 1
   - 2
   - 3

   - 1
   - 2
   - 3
   - 4

    import yaml

    data = yaml.load("""
    {
      "firstName": "John",
      # Woah comments
      "lastName": "Smith",
    }
    """, yaml.SafeLoader)

    python-version:
        - 3.8
        - 3.9
        - 3.10

    python-version:
        [3.8, 3.9, 3.10]