### 16.2.2.3 Hierachical ListBox

class `HList`()
  The HList widget can be used to display any data that have a hierarchical structure, for example, file system directory trees. The list entries are indented and connected by branch lines according to their places in the hierachy.

class `CheckList`()
  The CheckList widget displays a list of items to be selected by the user. CheckList acts similarly to the Tk checkbutton or radiobutton widgets, except it is capable of handling many more items than checkbuttons or radiobuttons.

class `Tree`()
  The Tree widget can be used to display hierachical data in a tree form. The user can adjust the view of the tree by opening or closing parts of the tree.