docs: def addFunction(self, func_code, from_file=''):
          """Add function 
          """
          if from_file:
              with open(from_file) as f:
                  func_code = f.read()
  
          root = self.etree
          t_execute = root.find('execute')
  
          if not t_execute :
              t_execute = ctree.SubElement(root, 'execute')
  
          t_execute.text = "\n\t![CDATA]{0:>5}]]\n\t".format(func_code.ljust(4))
  
          return True