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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):
 """List server credentials."""


    manager = SoftLayer.HardwareManager(env.client)
    hardware_id = helpers.resolve_id(manager.resolve_ids,
                                     identifier,
                                     'hardware')
    instance = manager.get_hardware(hardware_id)

    table = formatting.Table(['username', 'password'])
    for item in instance['softwareComponents']:
        if 'passwords' not in item:
            raise exceptions.SoftLayerError("No passwords found in softwareComponents")
        for credentials in item['passwords']:
            table.add_row([credentials.get('username', 'None'), credentials.get('password', 'None')])
    env.fout(table)