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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 quantitate(data):
 """CWL target for quantitation. XXX Needs to be split and parallelized by expression caller, with merging of multiple calls. """

    data = to_single_data(to_single_data(data))
    data = generate_transcript_counts(data)[0][0]
    data["quant"] = {}
    if "sailfish" in dd.get_expression_caller(data):
        data = to_single_data(sailfish.run_sailfish(data)[0])
        data["quant"]["tsv"] = data["sailfish"]
        data["quant"]["hdf5"] = os.path.join(os.path.dirname(data["sailfish"]), "abundance.h5")
    if ("kallisto" in dd.get_expression_caller(data) or "pizzly" in dd.get_fusion_caller(data, [])):
        data = to_single_data(kallisto.run_kallisto_rnaseq(data)[0])
        data["quant"]["tsv"] = os.path.join(data["kallisto_quant"], "abundance.tsv")
        data["quant"]["hdf5"] = os.path.join(data["kallisto_quant"], "abundance.h5")
    if (os.path.exists(os.path.join(data["kallisto_quant"], "fusion.txt"))):
        data["quant"]["fusion"] = os.path.join(data["kallisto_quant"], "fusion.txt")
    else:
        data["quant"]["fusion"] = None
    if "salmon" in dd.get_expression_caller(data):
        data = to_single_data(salmon.run_salmon_reads(data)[0])
        data["quant"]["tsv"] = data["salmon"]
        data["quant"]["hdf5"] = os.path.join(os.path.dirname(data["salmon"]), "abundance.h5")
    return [[data]]