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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 cli(env, identifier):
 """Unassigns a global IP from a target."""


    mgr = SoftLayer.NetworkManager(env.client)
    global_ip_id = helpers.resolve_id(mgr.resolve_global_ip_ids, identifier,
                                      name='global ip')
    mgr.unassign_global_ip(global_ip_id)