code: def __getitem__(self, name):
      obj = self
      for part in name.split("."):
          try:
              obj = getattr(obj, part)
          except AttributeError:
              raise KeyError(name)
      return obj
  
imports: import unittest
  import string
  from string import Template
label_desc: Use image node_id 1 for calling the Mapping obj's underlying member method code with example usage: obj.__getitem__(name) and returns: obj