using super

Hi

I'm trying to make a method call automatically to its super using this
syntax:

class A:
chained = ['pr']
def pr(self):
print 'Hello from A'

class B(A):
def pr(self):
print 'Hello from B'

chain(B, A)
b = B()
b.pr()

b.pr() will print
Hello from B
Hello from A

I'm doing it using the 'chained' attribute in class A, and with this
function:

def chain(cls, sup):
for m in dir(cls):
if callable(getattr(cls, m)) and m in cls.chained:
cm = getattr(cls, m)
def m2(*p):
cm(*p)
return getattr(sup, m)(*p)
setattr(cls, m, m2)
return cls

which seeks for all 'chained' methods and adjusts them accordingly.
(had there been class decorators the syntax would have been simpler,
something like

class A:
@make_chained
def pr():
print 'Hello from A'

@chained
class B:
def pr():
print 'Hello from B'
)


My problem is this: Currently I pass the base class to 'chain' -
chain(B, A)

I prefer to write
chain(B)

and let 'chain' use the super of B.

So:
def chain(cls):
for m in dir(cls):
if callable(getattr(cls, m)) and m in cls.chained:
print 'chaning', cls, m
cm = getattr(cls, m)
def m2(*p):
cm(*p)
return getattr(super(cls), m)(*p)
setattr(cls, m, m2)

This is probably wrong because I don't give the object instance to
super (I don't have it!) and I also get the error
TypeError: super() argument 1 must be type, not classobj

Can you please help me with this?

Thanks
iu2
.

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