Comparing UTF8 strings in python

I want to check that if the argumant s of function f1(s) receives some strings (that are in UTF8 ) in MyList then call function f2; But I cannot compare strings correctly.

def f1( s ):
    MyList = [ u"نامشخص".encode("utf-8") , u"Unknow".encode("utf-8")]
    for t in MyList:
        if( t == s.encode('utf-8') ):
            f2()
            return None
            break
        else:
            print t , " =?=" , s.encode("utf-8")
            print len(t), " =?=" , len(s)
    return s