class_docstr: Decorator to mark a function or class as deprecated.
  
  Issue a warning when the function is called/the class is instantiated and
  adds a warning to the docstring.
  
  The optional extra argument will be appended to the deprecation message
  and the docstring. Note: to use this with the default value for extra, put
  in an empty of parentheses:
  
  >>> from sklearn.utils import deprecated
  >>> deprecated() # doctest: +ELLIPSIS
  <sklearn.utils.deprecation.deprecated object at ...>
  
  >>> @deprecated()
  ... def some_function(): pass
code: def _update_doc(self, olddoc):
      newdoc = "DEPRECATED"
      if self.extra:
          newdoc = "%s: %s" % (newdoc, self.extra)
      if olddoc:
          newdoc = "%s\n\n%s" % (newdoc, olddoc)
      return newdoc
  
imports: import warnings
label_desc: Use image node_id 5 for calling the deprecated obj's underlying member method code with example usage: obj._update_doc(olddoc) and returns: newdoc