docs: protected File transformInputFile(File from) throws MojoExecutionException {
          // create a temp file
          File tempFile;
          try {
              tempFile = File.createTempFile("dotml-tmp", ".xml");
          } catch (IOException e) {
              throw new MojoExecutionException(
                      "error creating temp file to hold DOTML to DOT translation", e);
          }
          // perform an XSLT transform from the input file to the temp file
          Source xml = new StreamSource(from);
          Result result = new StreamResult(tempFile);
          try {
              Source xslt = new StreamSource(
                      getClass().getClassLoader().getResourceAsStream("dotml/dotml2dot.xsl"));
              transformerFactory.newTransformer(xslt).transform(xml, result);
          } catch (TransformerException e) {
              throw new MojoExecutionException(
                      String.format("error transforming %s from DOTML to DOT file", from), e);
          }
          // return the temp file
          return tempFile;
      }