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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 db_for_write(self, model, **hints):
 """ Attempts to write auth models go to duashttp. """

        if model._meta.app_label == 'duashttp':
            if not DUAS_ENABLE_DB_WRITE:
                raise ImproperlyConfigured(
                    "Set `DUAS_ENABLE_DB_WRITE` to True in your settings to enable "
                    "write operations on unity asset server database"
                )
            return DUAS_DB_ROUTE_PREFIX
        return None