Hooks advice to a function or method.
advise() is a decorator that takes a set of functions or methods and injects the decorated function in their place. There is no concept of before/after callbacks. Instead, the intercepting function is responsible for calling (or not) the intercepted function.
The "classic" logging example:
class A(object):
def a_function(self):
print 'a_function()'
@advise(A.a_function)
def logit(on, next, *args, **kwargs):
logging.debug('%r.%r(%r, %r)', on, next, args, kwargs)
return next(*args, **kwargs)
See the function documentation for more information.