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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_samples(in_file):
 """Retrieve samples present in a VCF file """

    with utils.open_gzipsafe(in_file) as in_handle:
        for line in in_handle:
            if line.startswith("#CHROM"):
                parts = line.strip().split("\t")
                return parts[9:]
    raise ValueError("Did not find sample header in VCF file %s" % in_file)