Loads a class looking for it in each module registered.

        :param classname: Class name you want to load.
        :type classname: str
        :return: Class object
        :rtype: type

def load_class(self, classname):
        """
        Loads a class looking for it in each module registered.

        :param classname: Class name you want to load.
        :type classname: str
        :return: Class object
        :rtype: type
        """

        module_list = self._get_module_list()

        for module in module_list:
            try:
                return import_class(classname, module.__name__)
            except (AttributeError, ImportError):
                pass

        raise ImportError("Class '{0}' could not be loaded.".format(classname))