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test_units.sol

pragma solidity >=0.4.0 <0.6.0;
contract UnitExample {
    
    function test() public {
        assert(1 wei == 1);
        assert(1 szabo == 1e12);
        assert(1 finney == 1e15);
        assert(1 ether == 1e18);
        
        //The suffix years has been removed in version 0.5.0 due to::
        //Take care if you perform calendar calculations using these units,  because not every year equals 365 days and not
        //even every day has 24 hours because of leap seconds. Due to the fact that leap seconds cannot be predicted, an exact
        //calendar library has to be updated by an external oracle
        assert(1 seconds == 1);
        assert(1 minutes == 60 seconds);
        assert(1 hours == 60 minutes);
        assert(1 days == 24 hours);
        assert(1 weeks == 7 days);
        
        
    }
}