href="../../preprocessing/custom/index.html#bluecast.preprocessing.custom.CustomPreprocessing" title="bluecast.preprocessing.custom.CustomPreprocessing"><span class="pre">bluecast.preprocessing.custom.CustomPreprocessing</span></a><span class="w"> </span><span class="p"><span class="pre">|</span></span><span class="w"> </span><span class="pre">None</span></span><span class="w"> </span><span class="o"><span class="pre">=</span></span><span class="w"> </span><span class="default_value"><span class="pre">None<