docs: def import_from_string(full_class_name):
          """return a class based on it's full class name"""
          s = full_class_name.split('.')
          class_name = s[-1]
          module_name = full_class_name[:-len(class_name)-1]
          module = importlib.import_module(module_name)
          # the class, it's common to spell with k as class is reserved
          klass = getattr(module, class_name)
          return klass