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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_mailbox(gandi, mailbox, output_keys, justify=16):
 """ Helper to output a mailbox information."""

    quota = 'quota' in output_keys
    responder = 'responder' in output_keys

    if quota:
        output_keys.pop(output_keys.index('quota'))

    if responder:
        output_keys.pop(output_keys.index('responder'))

    if 'aliases' in output_keys:
        mailbox['aliases'] = sorted(mailbox['aliases'])

    output_generic(gandi, mailbox, output_keys, justify)

    if 'fallback' in output_keys:
        output_line(gandi, 'fallback email', mailbox['fallback_email'],
                    justify)

    if quota:
        granted = mailbox['quota']['granted']
        if mailbox['quota']['granted'] == 0:
            granted = 'unlimited'
        output_line(gandi, 'quota usage',
                    '%s KiB / %s' % (mailbox['quota']['used'], granted),
                    justify)

    if responder:
        responder_status = 'yes' if mailbox['responder']['active'] else 'no'
        output_line(gandi, 'responder active', responder_status, justify)
        output_line(gandi, 'responder text', mailbox['responder']['text'],
                    justify)