class_docstr: Can be used to program the learning rate schedule of an `optim.base.Optimizer`.
code: def __repr__(self):
      return f"{self.__class__.__name__}({vars(self)})"
  
imports: from __future__ import annotations
  import abc
  import typing
  import numpy
  from river import base, optim, utils
label_desc: Use image node_id 2 for calling the Scheduler obj's underlying member method code with example usage: obj.__repr__() and returns: self, str, vars, str