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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def on_select_fit(self, event):
 """ Picks out the fit selected in the fit combobox and sets it to the current fit of the GUI then calls the select function of the fit to set the GUI's bounds boxes and alter other such parameters Parameters event : the wx.ComboBoxEvent that triggers this function Alters ------ current_fit, fit_box selection, tmin_box selection, tmax_box selection """

        fit_val = self.fit_box.GetValue()
        if self.s not in self.pmag_results_data['specimens'] or not self.pmag_results_data['specimens'][self.s] or fit_val == 'None':
            self.clear_boxes()
            self.current_fit = None
            self.fit_box.SetStringSelection('None')
            self.tmin_box.SetStringSelection('')
            self.tmax_box.SetStringSelection('')
        else:
            try:
                fit_num = list(
                    map(lambda x: x.name, self.pmag_results_data['specimens'][self.s])).index(fit_val)
            except ValueError:
                fit_num = -1
            self.pmag_results_data['specimens'][self.s][fit_num].select()
        if self.ie_open:
            self.ie.change_selected(self.current_fit)