Swift3 无法转换错误类型的值

我需要调试此错误的帮助

Cannot convert value of type 'PHContentEditingInput, [AnyHashable: Any]) -> Void' to expected argument type '(PHContentEditingInput?, [AnyHashable: Any]) -> Void'

代码如下：

asset?.requestContentEditingInput(with: nil, completionHandler: {(_ contentEditingInput: PHContentEditingInput, _ info: [AnyHashable: Any]) -> Void in
 self.storageRef.child(filePath).putFile(imageFile, metadata: metadata, completion: {(_ metadata: FIRStorageMetadata, _ error: Error?) -> Void in
  if error != nil {
   return
  }
 })
})

---

在

contenteditingput

的完成块中的

phcontenteditingput

之后放置

？

，因为它是可选类型

asset?.requestContentEditingInput(with: nil, completionHandler: 
{(_ contentEditingInput: PHContentEditingInput?, _ info: [AnyHashable: Any]) -> Void in

    self.storageRef.child(filePath).putFile(imageFile, metadata: metadata, completion: {(_ metadata: FIRStorageMetadata, _ error: Error?) -> Void in
        if error != nil {
            return
        }
    })
})