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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 _ask_path(cls, editor):
 """ Shows a QFileDialog and ask for a save filename. :return: save filename """

        try:
            filter = cls.get_filter(editor.mimetypes[0])
        except IndexError:
            filter = _('All files (*)')
        return QtWidgets.QFileDialog.getSaveFileName(
            editor, _('Save file as'), cls.default_directory, filter)