Select the true statements related to PEP 8 programming recommendations for code writing.

You should use the not ... is operator (e.g. if not spam is None:), rather than the is not operator (e.g. if spam is not None:), to increase readability.

You should make object type comparisons using the ismstanceQ method (e.g. if isinstance (obj, int) :) instead of comparing types directly (eg if type(obj) is type(i)).

You should write code in a way that favors the CPython implementation over PyPy, Cython. and Jython.

You should not write string literals that rely on significant trailing whitespaces as they may be visually indistinguishable, and certain editors may trim them