def get_modules(self, type_name):
        '''Getting modules by type name.

        Parameters
        ----------
        type_name : string
            Type name of the modules to be returned.

        Returns
        -------
        List of modules of given type name else empty list.
        '''
        modules = []
        for module in self:
            if module.__class__.__name__ == type_name:
                modules.append(module)
        return modules
Getting modules by type name.

        Parameters
        ----------
        type_name : string
            Type name of the modules to be returned.

        Returns
        -------
        List of modules of given type name else empty list.