class_docstr: This is used for formatting strings with values that need to be updated
  at that time, such as the current time or working directory.
code: def __format__(self, format_spec):
      return format(self(), format_spec)
  
file_path: catboost/contrib/python/ipython/py2/IPython/core/prompts.py
imports: from IPython.utils import py3compat
label_desc: Use image node_id 5 for calling the LazyEvaluate obj's underlying member method code with example usage: obj.__format__(format_spec) and returns: format