I created a dialogue with pyqt5, but 0xC0000409 error occurred. How can I solve this problem?

I was programming with python pyqt5, and I added the code below because I wanted user to customize the toolbar. So I decided to make a dialogue to choose from the functions in the menu bar.

app.py

from dialog.customize_tool import CustomizeTool
from PyQt5.QtWidgets import *
from PyQt5.QtGui import QIcon

...

        self.all_tools = {
            '프로그램 종료': self.exit_app, '게임 재시작': self.restart_game,
            '단어장 선택': self.select_vocab, '최근 단어장': self.recent_vocab,
            '툴바 설정': self.customize_tool_bar,
            '로그인': self.log_in, '계정 추가': self.add_account,
            '개발자 정보': self.show_developer_info, '도움말 보기': self.show_help_info
        }

...

    def customize_tool_bar(self):
        custom = QAction(QIcon('./sys_data/icon/custom.png'), '둘바 설정', self)
        custom.triggered.connect(self.get_custom_tools)
        custom.setStatusTip('툴바의 구성을 변경합니다.')
        custom.setShortcut('Ctrl+T')
        return custom

    def get_custom_tools(self):
        customize_tool = CustomizeTool(self.all_tools, self)
        customize_tool.exec_()
        self.tool_bar.clear()
        for i in customize_tool.user_select:
            for k, v in self.all_tools.items():
                if i == k:
                    self.tool_bar.addAction(v())
                    break

customize_tool.py

from PyQt5.QtWidgets import *


class CustomizeTool(QDialog):

    def __init__(self, all_tools: dict, parent):
        super(CustomizeTool, self).__init__(parent)

        v_box = QVBoxLayout()
        v_box.addWidget(self.customize_tool_group())

        self.tools = list(all_tools.keys())
        self.checkbox = [QCheckBox(i) for i in self.tools]
        self.user_select = tuple()

        self.setWindowTitle('툴바 설정')
        self.resize(200, 200)
        self.setLayout(v_box)
        self.show()

    def customize_tool_group(self):
        v_layout = QVBoxLayout()
        group_box = QGroupBox('툴바 설정')
        save_button = QPushButton('저장')

        for j in self.checkbox:
            v_layout.addWidget(j)
        v_layout.addWidget(save_button)
        group_box.setLayout(v_layout)

        save_button.clicked.connect(self.submit_checkbox_result())

        return group_box

    def submit_checkbox_result(self):
        self.user_select = tuple(i.text() for i in self.checkbox if i.isChecked())
        self.deleteLater()

There is no problem with anything else, but if I just run that function, Process finished with exit code -1073740791 (0xC0000409) error will occur. Why is that and how should I fix it?