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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 _match_serializers_by_query_arg(self, serializers):
 """Match serializer by query arg."""

        # if the format query argument is present, match the serializer
        arg_name = current_app.config.get('REST_MIMETYPE_QUERY_ARG_NAME')
        if arg_name:
            arg_value = request.args.get(arg_name, None)

            if arg_value is None:
                return None
            # Search for the serializer matching the format
            try:
                return serializers[
                    self.serializers_query_aliases[arg_value]]
            except KeyError:  # either no serializer for this format
                return None

        return None