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'.
  assert create_table_of_contents('MySQL')=='Yes'
  assert create_table_of_contents('PostgreSQL')=='Yes'
  assert create_table_of_contents('NoDatabase')=='No'
  assert create_table_of_contents('')=='No'
output: def create_table_of_contents(database_type):
      if database_type in ['MySQL', 'PostgreSQL']:
          return 'Yes'
      else:
          return 'No'