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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def update_session(fname=None):
 """Update current Scapy session from the file specified in the fname arg. params: - fname: file to load the scapy session from"""

    if fname is None:
        fname = conf.session
    try:
        s = six.moves.cPickle.load(gzip.open(fname, "rb"))
    except IOError:
        s = six.moves.cPickle.load(open(fname, "rb"))
    scapy_session = six.moves.builtins.__dict__["scapy_session"]
    scapy_session.update(s)
    update_ipython_session(scapy_session)