core data - How can I check which class declares a property from a NSAttributeDescription variable? -

myclassa inherits nsmanagedobject.

myclassb inherits myclassa.

myclassa has property, let's call classaprop.

myclassb has property, let's call classbprop.

i have instance of myclassb, myclassb. want loop through managed attributes of instance this:

[myclassb.entity.attributesbyname enumeratekeysandobjectsusingblock:^(nsstring *key, nsattributedescription *attribute, bool *stop) {}]} 

so within block, each attribute (classaprop, , classbprop) how can check if myclassa or myclassb declared properties.

within block, if @ [attribute description] see like:

proxy prop named classaprop on ed myclassb, real (<nsattributedescription: 0x7fce49536be0>), name classaprop, isoptional 0, istransient 0, entity myclassa, renamingidentifier classaprop, validation predicates ( ), warnings ( ), versionhashmodifier (null)  userinfo { }, attributetype 800 , attributevalueclassname nsnumber, defaultvalue 1 

internally seems it's possible access declaring class, can't seem find way access myself.

the way i've solved create instance of nsentitydescription of myclassa check against

[classadescription.attributesbyname.allkeys containsobject:thekey]; 

that way can filter out properties implemented myclassa aim.