input: Write a python function to load .npy files, plot data, and save the plots.
  assert os.path.exists('/nfs/a90/eepdw/Figures/EMBRACE/Diurnal/avg5216_land_latlon_bit_above_western_ghats.png')
  assert os.path.exists('/nfs/a90/eepdw/Figures/EMBRACE/Diurnal/avg5216_sea_latlon_bit_above_western_ghats.png')
  assert os.path.exists('/nfs/a90/eepdw/Figures/EMBRACE/Diurnal/avg5216_total_latlon_bit_above_western_ghats.png')
output: import os
  import numpy as np
  import matplotlib.pyplot as plt
  
  def load_and_plot_npy_files(land_file_path, sea_file_path, total_file_path, output_dir):
      # Load the .npy files
      land_data = np.load(land_file_path)
      sea_data = np.load(sea_file_path)
      total_data = np.load(total_file_path)
  
      # Plot and save the land data
      plt.figure()
      plt.imshow(land_data, cmap='viridis')
      plt.colorbar()
      plt.title('Land Data')
      land_output_path = os.path.join(output_dir, 'avg5216_land_latlon_bit_above_western_ghats.png')
      plt.savefig(land_output_path)
      plt.close()
  
      # Plot and save the sea data
      plt.figure()
      plt.imshow(sea_data, cmap='viridis')
      plt.colorbar()
      plt.title('Sea Data')
      sea_output_path = os.path.join(output_dir, 'avg5216_sea_latlon_bit_above_western_ghats.png')
      plt.savefig(sea_output_path)
      plt.close()
  
      # Plot and save the total data
      plt.figure()
      plt.imshow(total_data, cmap='viridis')
      plt.colorbar()
      plt.title('Total Data')
      total_output_path = os.path.join(output_dir, 'avg5216_total_latlon_bit_above_western_ghats.png')
      plt.savefig(total_output_path)
      plt.close()
  
  # Example usage
  land_file_path = '/path/to/land_data.npy'
  sea_file_path = '/path/to/sea_data.npy'
  total_file_path = '/path/to/total_data.npy'
  output_dir = '/nfs/a90/eepdw/Figures/EMBRACE/Diurnal/'
  
  load_and_plot_npy_files(land_file_path, sea_file_path, total_file_path, output_dir)