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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 load_query_string_data(request_schema, query_string_data=None):
 """ Load query string data using the given schema. Schemas are assumed to be compatible with the `PageSchema`. """

    if query_string_data is None:
        query_string_data = request.args

    request_data = request_schema.load(query_string_data)
    if request_data.errors:
        # pass the validation errors back in the context
        raise with_context(UnprocessableEntity("Validation error"), dict(errors=request_data.errors))
    return request_data.data