Assertion
If we want to validate something then we can put assertion. assert 0 <= price <= product['price'] If assertion condition doesn't satisfy, we'll get assertion error. Problem with the assertion is that our code can fail in the Production and stop working * assertion cant be in the tuple assert(1 == 2, 'This should fail') This condition is always True so you'll never get an assertion error. * Correct Statement: assert 1==2, ('this condition is not true')