def load_ipython_extension(ip):
    ip.register_magics(CacheMagics)
Infers user name and subject urn from self.urn.
dataset/ETHPy150Open rossant/ipycache/ipycache.py/load_ipython_extension--crossover with--dataset/ETHPy150Open google/grr/grr/lib/aff4_objects/security.py/ClientApproval.InferUserAndSubjectFromUrn