class_docstr: Elementwise inverse hyperbolic tangent function.
code: def check_type_forward(self, in_types):
      if hasattr(type_check, "_argname"):
          # typecheck._argname is introduced by Chainer v6
          type_check._argname(in_types, ("x",))
      (x_type,) = in_types
  
      type_check.expect(x_type.dtype.kind == "f")
  
file_path: chainerrl/chainerrl/functions/arctanh.py
imports: from chainer.backends import cuda
  from chainer import function_node
  from chainer import utils
  from chainer.utils import type_check
label_desc: Use image node_id 1 for calling the Arctanh obj's underlying member method code with example usage: obj.check_type_forward(in_types) without return types