docs: def show_info(self):
          """
          displays the doc string of the selected element
          """
          sender = self.sender()
          tree = sender.parent()
          index = tree.selectedIndexes()
          info = ''
          if index != []:
              index = index[0]
              name = str(index.model().itemFromIndex(index).text())
              self.selected_element_name = name
  
  
  
              if name in self.elements_old:
                  info = self.elements_old[name].__doc__
  
              #TODO: check if this is portable
              elif name in self.elements_from_file:
                  class_name = self.elements_from_file[name]['class']
                  if 'filepath' in self.elements_from_file[name]:
                      filepath = self.elements_from_file[name]['filepath']
                  if 'info' in self.elements_from_file[name]:
                      info = self.elements_from_file[name]['info']
                  #
                  # path_to_src_scripts = filepath[:filepath.find('\\pylabcontrol\\scripts\\')]
                  # module_name = path_to_src_scripts[path_to_src_scripts.rfind('\\')+1:]
                  # module = __import__('{:s}.pylabcontrol.{:s}'.format(module_name, self.elements_type), fromlist=[class_name])
                  # info = getattr(module, class_name).__doc__
  
  
  
              if info is None:
                  info = name
  
              if tree == self.tree_infile:
                  self.lbl_info.setText(info)
                  self.tree_loaded.clearSelection()
  
              elif tree == self.tree_loaded:
                  self.lbl_info.setText(info)
                  self.tree_infile.clearSelection()