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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 create_inputs(data):
 """Index input reads and prepare groups of reads to process concurrently. Allows parallelization of alignment beyond processors available on a single machine. Prepares a bgzip and grabix indexed file for retrieving sections of files. """

    from bcbio.pipeline import sample
    data = cwlutils.normalize_missing(data)
    aligner = tz.get_in(("config", "algorithm", "aligner"), data)
    # CRAM files must be converted to bgzipped fastq, unless not aligning.
    # Also need to prep and download remote files.
    if not ("files" in data and data["files"] and aligner and (_is_cram_input(data["files"]) or
                                                               objectstore.is_remote(data["files"][0]))):
        # skip indexing on samples without input files or not doing alignment
        if ("files" not in data or not data["files"] or data["files"][0] is None or not aligner):
            return [[data]]
    data["files_orig"] = data["files"]
    data["files"] = prep_fastq_inputs(data["files"], data)
    # preparation converts illumina into sanger format
    data["config"]["algorithm"]["quality_format"] = "standard"
    # Handle any necessary trimming
    data = utils.to_single_data(sample.trim_sample(data)[0])
    _prep_grabix_indexes(data["files"], data)
    data = _set_align_split_size(data)
    out = []
    if tz.get_in(["config", "algorithm", "align_split_size"], data):
        splits = _find_read_splits(data["files"][0], int(data["config"]["algorithm"]["align_split_size"]))
        for split in splits:
            cur_data = copy.deepcopy(data)
            cur_data["align_split"] = split
            out.append([cur_data])
    else:
        out.append([data])
    if "output_cwl_keys" in data:
        out = cwlutils.samples_to_records([utils.to_single_data(x) for x in out],
                                          ["files", "align_split", "config__algorithm__quality_format"])
    return out