docs: def addInput(self, key):
          """Add key to input : key, value or map
          """
          if key not in self.inputs:
              self.inputs.append(key)
  
          root = self.etree
          t_inputs = root.find('inputs')
  
          if not t_inputs :
              t_inputs = ctree.SubElement(root, 'inputs')
  
          t_inputs.append(key.etree)
  
          return True