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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 menu_text(self, request=None):
 """Return a string to use as link text when this page appears in menus."""

        source_field_name = settings.PAGE_FIELD_FOR_MENU_ITEM_TEXT
        if(
            source_field_name != 'menu_text' and
            hasattr(self, source_field_name)
        ):
            return getattr(self, source_field_name)
        return self.title