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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 _find_known(row):
 """Find variant present in known pathogenic databases. """

    out = []
    clinvar_no = set(["unknown", "untested", "non-pathogenic", "probable-non-pathogenic",
                      "uncertain_significance", "uncertain_significance", "not_provided",
                      "benign", "likely_benign"])
    if row["cosmic_ids"] or row["cosmic_id"]:
        out.append("cosmic")
    if row["clinvar_sig"] and not row["clinvar_sig"].lower() in clinvar_no:
        out.append("clinvar")
    return out