def METHOD_NAME(self, parent_arch: list) -> dict:
    """
    # ! Time performance is critical because called sequentialy
    Args:
        parent_arch (list(int)): [description]
    Returns:
        dict: [description]
    """
    i = self._random_state.choice(len(parent_arch))
    child_arch = parent_arch[:]
    range_upper_bound = self.space_list[i][1]
    elements = [j for j in range(range_upper_bound + 1) if j != child_arch[i]]
    # The mutation has to create a different search_space!
    sample = self._random_state.choice(elements, 1)[0]
    child_arch[i] = sample
    cfg = self.pb_dict.copy()
    cfg["arch_seq"] = child_arch
    return cfg