func (c *Checker) retrieveResultFromCache() *Result {
	if c.cachedResult != nil && c.cachedResult.expiration.After(time.Now()) {
		return c.cachedResult.result
	}
	return nil
}
retrieveResultFromCache returns the latest check result from cache, if any.
If the result is expired or none is available, this function will return nil.
package checker
import "time"