code: def init_state(self, param):
      xp = cuda.get_array_module(param.array)
      with cuda.get_device_from_array(param.array):
          self.state["ms"] = xp.zeros_like(param.array)
  
file_path: chainerrl/chainerrl/optimizers/rmsprop_async.py
imports: from chainer import cuda
  from chainer import optimizer
  import numpy
label_desc: Use image node_id 2 for calling the RMSpropAsyncRule obj's underlying member method code with example usage: obj.init_state(param) without return types