class_docstr: Runtime configuration options.
  
  Attributes
  ----------
  initialize : bool
      Automatic MPI initialization at import (default: True).
  threads : bool
      Request initialization with thread support (default: True).
  thread_level : {"multiple", "serialized", "funneled", "single"}
      Level of thread support to request (default: "multiple").
  finalize : None or bool
      Automatic MPI finalization at exit (default: None).
  fast_reduce : bool
      Use tree-based reductions for objects (default: True).
  recv_mprobe : bool
      Use matched probes to receive objects (default: True).
  irecv_bufsz : int
      Default buffer size in bytes for ``irecv()`` (default = 32768).
  errors : {"exception", "default", "abort", "fatal"}
      Error handling policy (default: "exception").
docstr: Return repr(self).
docstr_tok: ["Return","repr","(","self",")","."]
code: def __repr__(self):
      """Return repr(self)."""
      return f"<{__name__}.rc>"
  
label_desc: Use image node_id 4 for calling the Rc obj's underlying member method code with example usage: obj.__repr__() and returns: str, __name__, str