input: def create_data_visualization_dashboard():
      """Create a data visualization dashboard in Python using Matplotlib.
      
      Example:
      >>> create_data_visualization_dashboard()
      (displays the plot with title "My Data Visualization Dashboard")
      """
output:     import matplotlib.pyplot as plt
      import numpy as np
  
      # Generate some random data
      x = np.linspace(0, 10, 100)
      y1 = np.sin(x)
      y2 = np.cos(x)
  
      # Create the figure and axes
      fig, ax = plt.subplots(2, 1, figsize=(10, 8))
  
      # Plot the first dataset
      ax[0].plot(x, y1, label='sin(x)', color='blue')
      ax[0].set_title('Sine Wave')
      ax[0].legend()
  
      # Plot the second dataset
      ax[1].plot(x, y2, label='cos(x)', color='red')
      ax[1].set_title('Cosine Wave')
      ax[1].legend()
  
      # Set the overall title for the dashboard
      fig.suptitle('My Data Visualization Dashboard')
  
      # Display the plot
      plt.show()