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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 setup_datafind_from_pregenerated_lcf_files(cp, ifos, outputDir, tags=None):
 """ This function is used if you want to run with pregenerated lcf frame cache files. Parameters cp : ConfigParser.ConfigParser instance This contains a representation of the information stored within the workflow configuration files ifos : list of ifo strings List of ifos to get pregenerated files for. outputDir : path All output files written by datafind processes will be written to this directory. Currently this sub-module writes no output. tags : list of strings, optional (default=None) Use this to specify tags. This can be used if this module is being called more than once to give call specific configuration (by setting options in [workflow-datafind-${TAG}] rather than [workflow-datafind]). This is also used to tag the Files returned by the class to uniqueify the Files and uniqueify the actual filename. Returns -------- datafindcaches : list of glue.lal.Cache instances The glue.lal.Cache representations of the various calls to the datafind server and the returned frame files. datafindOuts : pycbc.workflow.core.FileList List of all the datafind output files for use later in the pipeline. """

    if tags is None:
        tags = []

    datafindcaches = []
    for ifo in ifos:
        search_string = "datafind-pregenerated-cache-file-%s" %(ifo.lower(),)
        frame_cache_file_name = cp.get_opt_tags("workflow-datafind",
                                                search_string, tags=tags)
        curr_cache = lal.Cache.fromfilenames([frame_cache_file_name],
                                             coltype=lal.LIGOTimeGPS)
        curr_cache.ifo = ifo
        datafindcaches.append(curr_cache)
    datafindouts = convert_cachelist_to_filelist(datafindcaches)

    return datafindcaches, datafindouts