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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add_user(self, recipient_email):
 """ Add user to encryption """

        self.import_key(emailid=recipient_email)
        emailid_list = self.list_user_emails()
        self.y = self.decrypt()
        emailid_list.append(recipient_email)
        self.encrypt(emailid_list=emailid_list)