code: def _getSyntaxByXmlFileName(self, xmlFileName):
          
          import qutepart.syntax.loader  # delayed import for avoid cross-imports problem
  
          with self._loadedSyntaxesLock:
              if not xmlFileName in self._loadedSyntaxes:
                  xmlFilePath = os.path.join(os.path.dirname(__file__), "data", "xml", xmlFileName)
                  syntax = Syntax(self)
                  self._loadedSyntaxes[xmlFileName] = syntax
                  qutepart.syntax.loader.loadSyntax(syntax, xmlFilePath)
  
              return self._loadedSyntaxes[xmlFileName]
docs: Get syntax by its xml file name