input: Write a function to determine if it is possible to create a HTML page that displays a table of contents from the data stored in a database. If it is possible return "Yes" else return "No". If the input is empty or not applicable return "N/A".
  assert create_table_of_contents("")=="N/A"
  assert create_table_of_contents("Database Connection")=="Yes"
  assert create_table_of_contents("No Database")=="No"
  assert create_table_of_contents("HTML, CSS, JS")=="Yes"
  assert create_table_of_contents("Invalid Input")=="N/A"
output: def create_table_of_contents(input_str):
      if not input_str or input_str == "Invalid Input":
          return "N/A"
      elif "Database" in input_str:
          return "Yes"
      else:
          return "No"