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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 fileserver(opts, backends):
    '''
    Returns the file server modules
    '''
    return LazyLoader(_module_dirs(opts, 'fileserver'),
                      opts,
                      tag='fileserver',
                      whitelist=backends,
                      pack={'__utils__': utils(opts)})