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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, postinstall, key):
 """Reload operating system on a server."""


    hardware = SoftLayer.HardwareManager(env.client)
    hardware_id = helpers.resolve_id(hardware.resolve_ids,
                                     identifier,
                                     'hardware')
    key_list = []
    if key:
        for single_key in key:
            resolver = SoftLayer.SshKeyManager(env.client).resolve_ids
            key_id = helpers.resolve_id(resolver, single_key, 'SshKey')
            key_list.append(key_id)
    if not (env.skip_confirmations or formatting.no_going_back(hardware_id)):
        raise exceptions.CLIAbort('Aborted')

    hardware.reload(hardware_id, postinstall, key_list)