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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 _summarize_call(parts):
 """Provide summary metrics on size and svtype for a SV call. """

    svtype = [x.split("=")[1] for x in parts[7].split(";") if x.startswith("SVTYPE=")]
    svtype = svtype[0] if svtype else ""
    start, end = _get_start_end(parts)
    return {"svtype": svtype, "size": int(end) - int(start)}