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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 get_hla(sample, cromwell_dir, hla_glob):
 """Retrieve HLA calls and input fastqs for a sample. """

    hla_dir = glob.glob(os.path.join(cromwell_dir, hla_glob, "align", sample, "hla"))[0]
    fastq = os.path.join(hla_dir, "OptiType-HLA-A_B_C-input.fq")
    calls = os.path.join(hla_dir, "%s-optitype.csv" % sample)
    return fastq, calls