code: func (m *lockingMap) Delete(key string) {
  	m.keyLocker.Lock(key)
  	defer m.keyLocker.Unlock(key)
  
  	m.lock.Lock()
  	defer m.lock.Unlock()
  
  	delete(m.data, key)
  }
docs: // Delete removes a key from the map if it exists. Returns nothing.