class_docstr: A ChainMap groups multiple dicts (or other mappings) together
  to create a single, updatable view.
  
  The underlying mappings are stored in a list.  That list is public and can
  be accessed / updated using the *maps* attribute.  There is no other state.
  
  Lookups search the underlying mappings successively until a key is found.
  In contrast, writes, updates, and deletions only operate on the first
  mapping.
docstr: New ChainMap or subclass with a new copy of maps[0] and refs to
  maps[1:]
docstr_tok: ["New","ChainMap","or","subclass","with","a","new","copy","of","maps","[","0","]","and","refs","to","maps","[","1",":","]"]
code: def copy(self):
      """
      New ChainMap or subclass with a new copy of maps[0] and refs to
      maps[1:]
      """
      return self.__class__(self.maps[0].copy(), *self.maps[1:])
  
imports: import sys
label_desc: Use image node_id 11 for calling the ChainMap obj's underlying member method code with example usage: obj.copy() and returns: self