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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 output_vlan(gandi, vlan, datacenters, output_keys, justify=10):
 """ Helper to output a vlan information."""

    output_generic(gandi, vlan, output_keys, justify)

    if 'dc' in output_keys:
        for dc in datacenters:
            if dc['id'] == vlan.get('datacenter_id',
                                    vlan.get('datacenter', {}).get('id')):
                dc_name = dc.get('dc_code', dc.get('iso', ''))
                break

        output_line(gandi, 'datacenter', dc_name, justify)