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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, sortby, datacenter, number, name, limit):
 """List VLANs."""


    mgr = SoftLayer.NetworkManager(env.client)

    table = formatting.Table(COLUMNS)
    table.sortby = sortby

    vlans = mgr.list_vlans(datacenter=datacenter,
                           vlan_number=number,
                           name=name,
                           limit=limit)
    for vlan in vlans:
        table.add_row([
            vlan['id'],
            vlan['vlanNumber'],
            vlan.get('name') or formatting.blank(),
            'Yes' if vlan['firewallInterfaces'] else 'No',
            utils.lookup(vlan, 'primaryRouter', 'datacenter', 'name'),
            vlan['hardwareCount'],
            vlan['virtualGuestCount'],
            vlan['totalPrimaryIpAddressCount'],
        ])

    env.fout(table)