new_contents: import matplotlib.pyplot as plt
  import pandas as pd
  
  df = pd.read_csv('reward.log')
  x = df.columns[0]
  y = df.columns[1]
  ax = df.plot(kind='scatter', x=x, y=y)
  df[y] = pd.rolling_mean(df[y], window=20)
  df.plot(kind='line', x=x, y=y, ax=ax)
  plt.show()
  
subject: add plot reward script