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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 _save_sign(self, filepath):
 """Sign so that the new file may be retrieved without safe mode"""


        if self.code_array.safe_mode:
            msg = _("File saved but not signed because it is unapproved.")
            try:
                post_command_event(self.main_window, self.StatusBarMsg,
                                   text=msg)
            except TypeError:
                # The main window does not exist any more
                pass

        else:
            try:
                self.sign_file(filepath)

            except ValueError, err:
                msg = "Signing file failed. " + unicode(err)
                post_command_event(self.main_window, self.StatusBarMsg,
                                   text=msg)