input: Write a function to create a command-line application in Python that stores customer data and allows customers to query by customer name. The function should accept a customer name as input and print the corresponding customer data. If the input is invalid, it should print an error message.
   
  import sys 
    
  def print_customer_data(name): 
      # Code for searching customer data by customer name and 
      # printing results 
      ...
  
  # Main function for the customer search application
  if __name__=="__main__": 
      # Get command line arguments 
      args = sys.argv 
      
      if len(args) == 2: 
          name = args[1]
          print_customer_data(name) 
      else: 
          print("Invalid arguments, please specify a customer name.")
  
  assert print_customer_data("Alice")==None
  assert print_customer_data("Bob")==None
  assert print_customer_data("Charlie")==None
  assert print_customer_data("")==None
output: def print_customer_data(name): 
      customers = {
          "Alice": "Customer data for Alice",
          "Bob": "Customer data for Bob",
          "Charlie": "Customer data for Charlie"
      }
      if name in customers:
          print(customers[name])
      else:
          print("Customer not found.")