@classmethod
def _add_nfa_states_from_queue(cls, nfa, current_states, current_state_name,
    dfa_states, dfa_transitions, dfa_final_states):
    """Add NFA states to DFA as it is constructed from NFA."""
    dfa_states.add(current_state_name)
    dfa_transitions[current_state_name] = {}
    if current_states & nfa.final_states:
        dfa_final_states.add(current_state_name)
