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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_login_credentials(args):
 """ Gets the login credentials from the user, if not specified while invoking the script. @param args: arguments provided to the script. """

  if not args.username:
    args.username = raw_input("Enter Username: ")
  if not args.password:
    args.password = getpass.getpass("Enter Password: ")