def _switchQueryStrandFlag(self):

        if self.strand == "-":
            self.strand = "+"
        else:
            self.strand = "-"
Test writing a vml with no cell data.
dataset/ETHPy150Open CGATOxford/cgat/obsolete/BlatTest.py/Match._switchQueryStrandFlag--crossover with--dataset/ETHPy150Open jmcnamara/XlsxWriter/xlsxwriter/test/vml/test_vml02.py/TestAssembleVml.test_assemble_xml_file