def enum_from_yaml(cls: Type[T_EnumFromYAML], constructor: Constructor, node: ruamel.yaml.nodes.ScalarNode) -> T_EnumFromYAML:
    """ Decode YAML representation.

    This is a mixin method for reading enum values from YAML. It needs to be added to the enum
    as a classmethod. See the module docstring for further information on this approach and how
    to implement it.

    Note:
        This method assumes that the name of the enumeration value was stored as a scalar node.

    Args:
        constructor: Constructor from the YAML object.
        node: Scalar node extracted from the YAML being read.
    Returns:
        The constructed YAML value from the name of the enumerated value.
    """
    # mypy doesn't like indexing to construct the enumeration.
    return cls[node.value]