def newClient(self):
        """Creates a new client.
        
        Variables
        --------
        client_name: expected input 'string'
        client_email: expected input 'string' with embedded @ symbol
        
        Exceptions
        ---------
        @raise exception:ClientException error for invalid input 
        """
        client_name = input("Please enter the client's name: ")
        client_email = input("Please enter the client's email address: ")

        if re.match("[0-9]", client_name) is not None:
            raise ClientException("Client name can only contain characters")
        if client_email.find("@") >= 0:
            self.last_client_id += 1
            #creates client
            my_client = Client(self.last_client_id, client_name, client_email)
            #puts created clients in the diction clients
            self.clients[str(my_client.getID())] = my_client
            return my_client
        else:
            raise ClientException(
                "Client cannot be created; invalid email address")
    def newClient(self):
        client_name = input("Please enter the client's name: ")
        client_email = input("Please enter the client's email address: ")

        if client_email.find("@") >= 0:
            self.last_client_id += 1
            my_client = Client(self.last_client_id, client_name, client_email)
            self.clients[str(my_client.getID())] = my_client
            return my_client
        else:
            raise ClientException(
                "Client cannot be created; invalid email address")