code: def log1p(x):
      """Elementwise natural logarithm plus one function.
  
      Args:
          x (:class:`~chainer.Variable` or :ref:`ndarray`): Input variable.
  
      Returns:
          ~chainer.Variable: Output variable.
      """
      return Log1p().apply((x,))[0]
  
file_path: chainer/chainer/functions/math/logarithm_1p.py
imports: import numpy
  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 a global function with example usage: log1p(x) and returns: Log1p