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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 power_on(env, identifier):
 """Power on a virtual server."""


    vsi = SoftLayer.VSManager(env.client)
    vs_id = helpers.resolve_id(vsi.resolve_ids, identifier, 'VS')
    env.client['Virtual_Guest'].powerOn(id=vs_id)