Consider the following premises. There is at least one z for which if z were a police officer, then z is a politician. For all z, z is a sailor if and only if z is a politician. For all z, if z were a sailor, then z is a police officer. Can we infer the following from them? For all z, if is not true that z is a sailor if and only if z is a politician.
That contradicts the premises. Therefore the answer is no.