func (reg *Registry) Lookup(mimetype string) (codec Codec, ok bool) {
	reg.mutex.RLock()
	codec, ok = reg.codecs[mimetype]
	reg.mutex.RUnlock()
	return
}
func (reg *Registry) Lookup(mimetype string) (codec Codec, ok bool) {
	reg.mutex.RLock()
	codec, ok = reg.codecs[mimetype]
	reg.mutex.RUnlock()
	return
}
func ( reg * Registry ) Lookup ( mimetype string ) ( codec Codec , ok bool ) { reg . mutex . RLock ( ) codec , ok = reg . codecs [ mimetype ] reg . mutex . RUnlock ( ) return }
// Lookup returns the codec associated with mimetype, ok is set to true or false
// based on whether a codec was found.
Lookup returns the codec associated with mimetype ok is set to true or false based on whether a codec was found .