@app.route('/export_data', methods=['GET', 'POST'])
def export_data():
    cnx = mariadb.connect(user='root', password='', database='test')
    cursor = cnx.cursor()

    query = "SELECT ID, data, cred, deb, dsc, valor FROM base_teste"

    cursor.execute(query)
    rows = cursor.fetchall()
    desc = cursor.description
    cnx.close()


    lista = [dict(itertools.izip([col[0] for col in desc], row))
        for row in rows]

    return lista

@app.route('/get_data', methods=['GET', 'POST'])
def get_data():
    results = export_data()
    return json.dumps(results)

$(document).ready(function() {
    $('#examplo').DataTable( {
        "ajax": {
            "url": "/get_data",
            "dataSrc": "",
        },
    } );
} );