There is nothing special you need to so to set unicode values. unicode objects in python are not utf-8, they are either utf-16 or ucs-4 depending on compile time options.
Where are you getting u_genre from?
If you want to set a unicode value pass in a unicode string not a bytestring. That means,
Code:
if isintance(u_genre, bytes):
u_genre = u_genre.decode('utf-8')