'Tag the method as instrumented.
This tag will prevent any decoration from being applied to the
method. Use this if you are orchestrating your own calls to
:func:`.collection_adapter` in one of the basic SQLAlchemy
interface methods, or to prevent an automatic ABC method
decoration from wrapping your implementation::
# normally an \'extend\' method on a list-like class would be
# automatically intercepted and re-implemented in terms of
# SQLAlchemy events and append().  your implementation will
# never be called, unless:
@collection.internally_instrumented
def extend(self, items): ...'

@staticmethod
def internally_instrumented(fn):

    fn._sa_instrumented = True
    return fn
