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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 delete_user(self, recipient_email):
 """ Remove user from encryption """

        emailid_list = self.list_user_emails()
        if recipient_email not in emailid_list:
            raise Exception("User {0} not present!".format(recipient_email))
        else:
            emailid_list.remove(recipient_email)
            self.y = self.decrypt()
            self.encrypt(emailid_list=emailid_list)