code: func GetBoolean(data []byte, keys ...string) (val bool, err error) {
  	v, t, _, e := Get(data, keys...)
  
  	if e != nil {
  		return false, e
  	}
  
  	if t != Boolean {
  		return false, fmt.Errorf("Value is not a boolean: %s", string(v))
  	}
  
  	return ParseBoolean(v)
  }
docs: // GetBoolean returns the value retrieved by `Get`, cast to a bool if possible.
  // The offset is the same as in `Get`.
  // If key data type do not match, it will return error.