func (m *Map) Exist(key string) bool {
	_, ok := m.Load()[KeyNamed(key)]
	return ok
}
Exist check if values map exist a key.
package paladin
import (
	"strings"
	"sync/atomic"
)
func KeyNamed(key string) string {
	return strings.ToLower(key)
}
type Map struct {
	values atomic.Value
}
func (m *Map) Store(values map[string]*Value) {
	dst := make(map[string]*Value, len(values))
	for k, v := range values {
		dst[KeyNamed(k)] = v
	}
	m.values.Store(dst)
}
func (m *Map) Load() map[string]*Value {
	src := m.values.Load().(map[string]*Value)
	dst := make(map[string]*Value, len(src))
	for k, v := range src {
		dst[k] = v
	}
	return dst
}