code: def plot_time_elapsed(
      filename, elapsed=False, unit="s", plot_kwargs=None
  ):
      """Plot series data from MonitorTimeElapsed output text file.
  
      Args:
          filename (str): Path to *.series.txt file produced by :obj:`~nnabla.MonitorSeries` class.
          elapsed (bool): If ``True``, it plots the total elapsed time.
          unit (str):
              Time unit chosen from ``'s'``, ``'m'``, ``'h'``, or ``'d'``.
          plot_kwags (dict, optional):
              Keyward arguments passed to :function:`matplotlib.pyplot.plot`.
  
      Note:
          matplotlib package is required.
  
      """
      import matplotlib.pyplot as plt
  
      if plot_kwargs is None:
          plot_kwargs = {}
  
      data_column = 3 if elapsed else 1
      data = np.genfromtxt(
          filename,
          dtype="i8,f4",
          usecols=(0, data_column),
          names=["k", "v"],
      )
      index = data["k"]
      values = data["v"]
      if unit == "s":
          pass
      elif unit == "m":
          values /= 60
      elif unit == "h":
          values /= 3600
      elif unit == "d":
          values /= 3600 * 24
      else:
          raise ValueError(
              "The argument `unit` must be chosen from {s|m|h|d}."
          )
      plt.plot(index, values, **plot_kwargs)
  
imports: from __future__ import print_function
  import numpy
  import os
  import time
  from nnabla.logger import logger
label_desc: Use image node_id 3 for calling a global function with example usage: plot_time_elapsed(filename, elapsed, unit, plot_kwargs) without return types