code: func fixMemorySwappiness(resources *containertypes.Resources) {
  	if resources.MemorySwappiness != nil && *resources.MemorySwappiness == -1 {
  		resources.MemorySwappiness = nil
  	}
  }
docs: // because the CLI sends a -1 when it wants to unset the swappiness value
  // we need to clear it on the server side