code: def _simple_string_value(tree, kind, name):
      
      query = ".//{kind}[@Name='{name}']/Value".format(kind=kind, name=name)
      return tree.find(query).text
docs: base function for extracting a simple parameter value.
      :param tree: the parameters tree.
      :param kind: the xml-tag name of the parameter.
      :param name: the name of the parameter.
      :returns value: the content of the parameter 'Value' as string.