code: import os
  import matplotlib
  import json
  from datetime import datetime
  from matplotlib import pyplot
  
  
  def show_results_graph(timer, name=None):
      with (open('light_plot.json', 'r')) as f:
          data = json.load(f)
  
      with (open('light_plot_imporved.json', 'r')) as f:
          data_improved = json.load(f)
  
      os.remove('light_plot.json')
      os.remove('light_plot_imporved.json')
      x = []
      y = []
      x_improved = []
      y_improved = []
  
      for item in data:
          date = datetime.strptime(item['x'], "%Y-%m-%d %H:%M:%S")
          x.append(date)
          if item['y'] == 1:
              y.append(item['y'] + 0.1)  # to distinct normal light and improved light states
          else:
              y.append(item['y'])
  
      for item in data_improved:
          date = datetime.strptime(item['x'], "%Y-%m-%d %H:%M:%S")
          x_improved.append(date)
          y_improved.append(item['y'])
  
      dates_normal = matplotlib.dates.date2num(x)
      dates_improved = matplotlib.dates.date2num(x_improved)
  
      matplotlib.pyplot.plot_date(dates_normal, y, 'b-', label="Regular data", linewidth=2)
      matplotlib.pyplot.plot_date(dates_improved, y_improved, 'b-', color="red", label="Possible improvement", linewidth=2)
      pyplot.title("Compare actual data and possible improvement ({} minutes)".format(timer))
      pyplot.legend()
      if name:
          pyplot.savefig("result.png")
      pyplot.show()
  
apis: matplotlib.pyplot.plot_date matplotlib.pyplot.legend matplotlib.pyplot.savefig matplotlib.pyplot.show matplotlib.dates.date2num