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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_start_end(parts, index=7):
 """Retrieve start and end for a VCF record, skips BNDs without END coords """

    start = parts[1]
    end = [x.split("=")[-1] for x in parts[index].split(";") if x.startswith("END=")]
    if end:
        end = end[0]
        return start, end
    return None, None