function start_Stage0_Trade() internal
        onlyAdmin
    {
        if(sale_status!= Sale_Status.Public_Allowed_To_Trade_STATUS) revert();
        
        

        uint32 stage0_locked_year= 1;
 
        bool is_debug= false; 
        if(is_debug==false && block.timestamp <  stage0_locked_year*365*24*60*60
            + when_public_allowed_to_trade_started  )  
	      revert();
        if(is_debug==true  && block.timestamp <  stage0_locked_year*10*60
            + when_public_allowed_to_trade_started  )  
	      revert();
	      
        sale_status= Sale_Status.Stage0_Allowed_To_Trade_STATUS;
        when_stage0_allowed_to_trade_started= block.timestamp;
        emit StartTradeStage0SaleTokens(block.timestamp); 
    }