code: 
  import matplotlib.pyplot as plt
  import numpy as np
  import seaborn as sns
  
  def show_corr(X, mask=True, figsize=(7,7)):
      fig, ax = plt.subplots(figsize=figsize)
      corr = X.corr()
      mask = np.triu(np.ones_like(corr, dtype=bool)) if mask else np.ones_like(corr, dtype=bool)
      sns.heatmap(corr, mask=mask, square=True, annot=True, ax=ax)
      plt.show()
apis: matplotlib.pyplot.show numpy.ones_like matplotlib.pyplot.subplots