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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, context_id, friendly_name, remote_peer, preshared_key, phase1_auth, phase1_crypto, phase1_dh, phase1_key_ttl, phase2_auth, phase2_crypto, phase2_dh, phase2_forward_secrecy, phase2_key_ttl):
 """Update tunnel context properties. Updates are made atomically, so either all are accepted or none are. Key life values must be in the range 120-172800. Phase 2 perfect forward secrecy must be in the range 0-1. A separate configuration request should be made to realize changes on network devices. """

    manager = SoftLayer.IPSECManager(env.client)
    succeeded = manager.update_tunnel_context(
        context_id,
        friendly_name=friendly_name,
        remote_peer=remote_peer,
        preshared_key=preshared_key,
        phase1_auth=phase1_auth,
        phase1_crypto=phase1_crypto,
        phase1_dh=phase1_dh,
        phase1_key_ttl=phase1_key_ttl,
        phase2_auth=phase2_auth,
        phase2_crypto=phase2_crypto,
        phase2_dh=phase2_dh,
        phase2_forward_secrecy=phase2_forward_secrecy,
        phase2_key_ttl=phase2_key_ttl
    )
    if succeeded:
        env.out('Updated context #{}'.format(context_id))
    else:
        raise CLIHalt('Failed to update context #{}'.format(context_id))