there is also another way of doing it by looping through the items in d. this doesn’t have the same assuption that they will get stored in c.__dict__ which isn’t always true.
d = {'bar': 456}
for key,value in d.items():
setattr(c,key,value)
or you could write a update method as part of MyClass so that c.update(d) works like you expected it to.
def update(self,newdata):
for key,value in newdata.items():
setattr(self,key,value)
check out the help for setattr
setattr(...) setattr(object, name, value) Set a named attribute on an object; setattr(x, 'y', v) is equivalent to ''x.y = v''.