Unpacking refers to restoring the encrypted theme to the original common theme. In Huawei's encryption system, unpacking operation needs to use corresponding keys and algorithms to decrypt. The following is a simple example of unpacking process:

Get the encryption theme: First, you need to get the encryption theme. This is usually achieved by receiving encrypted mail or messages.

Obtain decryption key: The unpacking operation needs to use the correct decryption key. You need to obtain the correct decryption key from the sender or the relevant security authority. This may involve the authentication and authorization process.

Perform decryption operation: use the obtained decryption key to decrypt the encrypted subject with the correct decryption algorithm. This usually involves decryption using a symmetric key encryption algorithm (such as AES) or an asymmetric key encryption algorithm (such as RSA).

Get plaintext theme: After the decryption operation is completed, the original plaintext theme will be obtained. This is the final result of unpacking operation.

Please note that unpacking may involve more complicated steps and security measures, depending on the encryption system and protocol used. In practice, it is recommended to follow relevant security guidelines and best practices to ensure the security and confidentiality of data.