code: def build_description(node=None):
      
      if node is None:
          from logging_tree.nodes import tree
          node = tree()
      return '\n'.join([ line.rstrip() for line in describe(node) ]) + '\n'
docs: Return a multi-line string describing a `logging_tree.nodes.Node`.
  
      If no `node` argument is provided, then the entire tree of currently
      active `logging` loggers is printed out.