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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 ext_pillar(minion_id,
               pillar,  # pylint: disable=W0613
               command):  # pylint: disable=W0613
    '''
    Read in the generated libvirt keys
    '''
    key_dir = os.path.join(
            __opts__['pki_dir'],
            'libvirt',
            minion_id)
    cacert = os.path.join(__opts__['pki_dir'],
                          'libvirt',
                          'cacert.pem')
    if not os.path.isdir(key_dir):
        # No keys have been generated
        gen_hyper_keys(minion_id,
                       pillar.get('ext_pillar_virt.country', 'US'),
                       pillar.get('ext_pillar_virt.st', 'Utah'),
                       pillar.get('ext_pillar_virt.locality',
                                  'Salt Lake City'),
                       pillar.get('ext_pillar_virt.organization', 'Salted'),
                       pillar.get('ext_pillar_virt.expiration_days', '365')
                       )
    ret = {}
    for key in os.listdir(key_dir):
        if not key.endswith('.pem'):
            continue
        fn_ = os.path.join(key_dir, key)
        with salt.utils.files.fopen(fn_, 'r') as fp_:
            ret['libvirt.{0}'.format(key)] = \
                salt.utils.stringutils.to_unicode(fp_.read())
    with salt.utils.files.fopen(cacert, 'r') as fp_:
        ret['libvirt.cacert.pem'] = \
            salt.utils.stringutils.to_unicode(fp_.read())
    return ret