concept Private_Key
  purpose provide secure control and ownership of a public key, enabling the creation of digital signatures.

  state
    user_handle: String
    private_key: String

  actions
    generatePrivateKey()
      pre true
      // Additional logic to generate a private key
      set private_key to generatedPrivateKey()

    retrievePrivateKey()
      pre true
      // Additional logic to retrieve the user's private key
      set private_key to storedPrivateKey()

    storePrivateKey()
      pre true
      // Additional logic to store the user's private key securely

  operational principle
    after generatePrivateKey(), a private key is generated and associated with the user
    after retrievePrivateKey(), the user's private key is retrieved
    after storePrivateKey(), the user's private key is securely stored