How to use the gooey.gui.lang.i18n function in Gooey

def success():
      self._header.SetLabel(i18n._('finished_title'))
      self._subheader.SetLabel(i18n._('finished_msg'))
      self._running_img.Hide()
      self._check_mark.Show()
      self.Layout()

container.Add(wx_util.h0(self, self.title), 0, wx.LEFT | wx.RIGHT, PADDING)
      container.AddSpacer(30)

    if self.widgets.required_args:
      container.Add(wx_util.h1(self, i18n._("required_args_msg")), 0, wx.LEFT | wx.RIGHT, PADDING)
      container.AddSpacer(5)
      container.Add(wx_util.horizontal_rule(self), *STD_LAYOUT)
      container.AddSpacer(20)

      self.CreateComponentGrid(container, self.widgets.required_args, cols=self._num_req_cols)

      container.AddSpacer(10)

    if self.widgets.optional_args:
      # container.AddSpacer(10)
      container.Add(wx_util.h1(self, i18n._("optional_args_msg")), 0, wx.LEFT | wx.RIGHT, PADDING)
      container.AddSpacer(5)
      container.Add(wx_util.horizontal_rule(self), *STD_LAYOUT)
      container.AddSpacer(20)

      self.CreateComponentGrid(container, self.widgets.optional_args, cols=self._num_opt_cols)

    self.SetSizer(container)

def _init_components(self):
    self.cancel_button      = self.button(i18n._('cancel'),  wx.ID_CANCEL,  event_id=int(events.WINDOW_CANCEL))
    self.stop_button        = self.button(i18n._('stop'),    wx.ID_OK,      event_id=int(events.WINDOW_STOP))
    self.start_button       = self.button(i18n._('start'),   wx.ID_OK,      event_id=int(events.WINDOW_START))
    self.close_button       = self.button(i18n._("close"),   wx.ID_OK,      event_id=int(events.WINDOW_CLOSE))
    self.restart_button     = self.button(i18n._('restart'), wx.ID_OK,      event_id=int(events.WINDOW_RESTART))
    self.edit_button        = self.button(i18n._('edit'),    wx.ID_OK,      event_id=int(events.WINDOW_EDIT))

    self.running_animation  = wx.animate.GIFAnimationCtrl(self, -1, image_repository.loader)

    self.buttons = [self.cancel_button, self.start_button, self.stop_button, self.close_button, self.restart_button, self.edit_button]

def _init_components(self):
    self.cancel_button      = self.button(i18n._('cancel'),  wx.ID_CANCEL,  event_id=int(events.WINDOW_CANCEL))
    self.stop_button        = self.button(i18n._('stop'),    wx.ID_OK,      event_id=int(events.WINDOW_STOP))
    self.start_button       = self.button(i18n._('start'),   wx.ID_OK,      event_id=int(events.WINDOW_START))
    self.close_button       = self.button(i18n._("close"),   wx.ID_OK,      event_id=int(events.WINDOW_CLOSE))
    self.restart_button     = self.button(i18n._('restart'), wx.ID_OK,      event_id=int(events.WINDOW_RESTART))
    self.edit_button        = self.button(i18n._('edit'),    wx.ID_OK,      event_id=int(events.WINDOW_EDIT))

    self.progress_bar  = wx.Gauge(self, range=100)

    self.buttons = [self.cancel_button, self.start_button,
                    self.stop_button, self.close_button,
                    self.restart_button, self.edit_button]

def running():
      self._header.SetLabel(i18n._("running_title"))
      self._subheader.SetLabel(i18n._('running_msg'))
      self._check_mark.Hide()
      self._settings_img.Hide()
      self._running_img.Show()
      self._error_symbol.Hide()
      self.Layout()

def _init_components(self):
    self.cancel_button      = self.button(i18n._('cancel'),  wx.ID_CANCEL,  event_id=int(events.WINDOW_CANCEL))
    self.stop_button        = self.button(i18n._('stop'),    wx.ID_OK,      event_id=int(events.WINDOW_STOP))
    self.start_button       = self.button(i18n._('start'),   wx.ID_OK,      event_id=int(events.WINDOW_START))
    self.close_button       = self.button(i18n._("close"),   wx.ID_OK,      event_id=int(events.WINDOW_CLOSE))
    self.restart_button     = self.button(i18n._('restart'), wx.ID_OK,      event_id=int(events.WINDOW_RESTART))
    self.edit_button        = self.button(i18n._('edit'),    wx.ID_OK,      event_id=int(events.WINDOW_EDIT))

    self.running_animation  = wx.animate.GIFAnimationCtrl(self, -1, image_repository.loader)

    self.buttons = [self.cancel_button, self.start_button, self.stop_button, self.close_button, self.restart_button, self.edit_button]

def _init_components(self):
    self.text = wx.StaticText(self, label=i18n._("status"))
    self.cmd_textbox = wx.TextCtrl(
      self, -1, "",
      style=wx.TE_MULTILINE | wx.TE_READONLY | wx.TE_RICH)
    if self.build_spec.get('monospace_display'):
      pointsize = self.cmd_textbox.GetFont().GetPointSize()
      font = wx.Font(pointsize, wx.FONTFAMILY_MODERN,
                   wx.FONTWEIGHT_NORMAL, wx.FONTWEIGHT_BOLD, False)
      self.cmd_textbox.SetFont(font)

def __init__(self):
    self.button_text = i18n._('browse')
    self.parent = None
    self.widget = None
    self.button = None

def __init__(self, data):
    self.data = data

    # parent
    self.panel = None

    self.button_text = i18n._('browse')

    # Widgets
    self.title = None
    self.help_msg = None
    self.text_box = None
    self.button = None
    self.panel = None

def build_app(build_spec):
  app = wx.App(False)

  i18n.load(build_spec['language_dir'], build_spec['language'], build_spec['encoding'])
  imagesPaths = image_repository.loadImages(build_spec['image_dir'])
  gapp = GooeyApplication(merge(build_spec, imagesPaths))
  # wx.lib.inspection.InspectionTool().Show()
  gapp.Show()
  return app