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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, function, **kwargs):
    '''
    Grabs external pillar data based on configured function
    '''
    if function.startswith('_') or function not in globals():
        return {}
    # Call specified function to pull redis data
    return globals()[function](minion_id, pillar, **kwargs)