Example# 3 from Part-1 Rice's Theorem from https://gatecse.in/rices-theorem/ states as follows

*(3) L(M) is recognized by a TM having even number of states*

*Sol: This is a trivial property. This set equals the set of recursively enumerable languages.*

*According to the previous examples, if i can find a Turing Machine which says Yes and a Turing Machine which says No, so i'll choose T*_{NO }as **PHI **(Empty String) and T_{YES} as a TM which accepts even number of states, then is it true that my L(M) is undecidable as the property is non-trivial, is my Reasoning correct ?

It seems like i can find T_{YES} and T_{NO} for every property then?

Can someone give me an example for which T_{YES} and T_{NO} cannot be found and let me know if my approach is correct ?