You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: scannerc.go
    path of file: ./repos/podman/vendor/gopkg.in/yaml.v2
    
    the code of the file until where you have to start completion: package yaml

import (
	"bytes"
	"fmt"
)

// Introduction
// ************
//
// The following notes assume that you are familiar with the YAML specification
// (http://yaml.org/spec/1.2/spec.html).  We mostly follow it, although in
// some cases we are less restrictive that it requires.
//
// The process of transforming a YAML s
    
func yaml_simple_key_is_valid(parser *yaml_parser_t, simple_key *yaml_simple_key_t) (valid, ok bool) {
	if !simple_key.possible {
		return false, true
	}

	// The 1.2 specification says:
	//
	//     "If the ? indicator is omitted, parsing needs to see past the
	//     implicit key to recognize it as such. To limit the amount of
	//     lookahead required, the “:” indicator must appear at most 1024
	//     Unicode characters beyond the start of the key. In addition, the key
	//     is restricted to a single line."
	//
	if simple_key.mark.line < parser.mark.line || simple_key.mark.index+1024 < parser.mark.index {
		// Check if the potential simple key to be removed is required.
		if simple_key.required {
			return false, yaml_parser_set_scanner_error(parser,
				"while scanning a simple key", simple_key.mark,
				"could not find expected ':'")
		}
		simple_key.possible = false
		return false, true
	}
	return true, true
}