code: func (c *Cache) Delete(key Key) {
  	logger.Debugf("%s - Deleting cache key", key.String())
  	value, ok := c.m.Load(key.String())
  	if ok {
  		c.close(key.String(), value.(future))
  		c.m.Delete(key.String())
  	}
  }
docs: // Delete does the following:
  // - calls Close on all values that implement a Close() function
  // - deletes key from the cache