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 application should take a customer name as a command-line argument and print the corresponding customer data if found. If the provided arguments are invalid or if the customer name is not found, it should print an appropriate 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") is None
  assert print_customer_data("Bob") is None
  assert print_customer_data("Charlie") is None
  assert print_customer_data("David") is None
  assert print_customer_data("") is None
output: def print_customer_data(name):
      customers = {
          "Alice": "Customer data for Alice",
          "Bob": "Customer data for Bob",
          "Charlie": "Customer data for Charlie",
          "David": "Customer data for David"
      }
      if name in customers:
          print(customers[name])
      else:
          print("Customer not found.")