contarct code class

pragma solidity ^0.4.24;

contract bank_ds {
    mapping ( address => bool ) public bankRegis;
    mapping ( address => bool ) public owner;
    
    modifier isOwner(){
        require(owner[msg.sender] == true);
        _;
    }
    event bankadded( address a);
}
contract bank is bank_ds {
    
    constructor()
        public
    {
        State.Created;
        owner[msg.sender] = true;
    }
    
    function addOwner ( address a) 
        isOwner
        public
    {
        owner[a] = true;
    }
    
    function addBank ( address a) 
        isOwner
        public
    {
        bankRegis[a] = true;
        emit bankadded(a);
    }
    
}

contract registry_ds { 
    mapping ( string => bool )  aadharKYC;
    bank bankRegistry;
    address public bankRegis;

    modifier isValidBank ( ){
        require(bankRegistry.bankRegis(msg.sender) == true);
        _;
    }

}

contract registry is registry_ds {
    
    constructor(address bankR)
        public
    {
        bankRegistry = bank(bankR);
    }
    
    function set ( string no ) 
        isValidBank        
        public
    {
        aadharKYC[no] = true;
    }

    function get ( string no ) 
        isValidBank        
        public
        view
        returns ( bool state )
    {
        state =aadharKYC[no];
    }

}

contract creator { 
    
    registry r1;
    bank b1;
    address public bankR;
    address public regis;
    
    address public owner;
    bool public state = false;
    
    modifier isOwner(){
        require(msg.sender == owner);
        _;
    }

    modifier isFalse(){
        require(state == false);
        _;
    }
    
    constructor ()
        public
    {
        owner = msg.sender;  
        state = false;
    }
    
    function createBank()
        isOwner
        isFalse
        public
    {
        b1 = new bank();
        bankR = address(b1);
    }
    
       
}