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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, *args, **kwargs):
    '''
    Compile pillar data
    '''
    # Node definitions path will be retrieved from args (or set to default),
    # then added to 'salt_data' dict that is passed to the 'get_pillars'
    # function. The dictionary contains:
    #     - __opts__
    #     - __salt__
    #     - __grains__
    #     - __pillar__
    #     - minion_id
    #     - path
    #
    # If successful, the function will return a pillar dict for minion_id.

    # If path has not been set, make a default
    for i in args:
        if 'path' not in i:
            path = '/srv/saltclass'
            args[i]['path'] = path
            log.warning('path variable unset, using default: %s', path)
        else:
            path = i['path']

    # Create a dict that will contain our salt dicts to pass it to reclass
    salt_data = {
        '__opts__': __opts__,
        '__salt__': __salt__,
        '__grains__': __grains__,
        '__pillar__': pillar,
        'minion_id': minion_id,
        'path': path
    }

    return sc.get_pillars(minion_id, salt_data)