code: def list_content_types(repo):
      
      schema_files = glob.glob(
          os.path.join(repo.working_dir, '_schemas', '*.avsc'))
      return [os.path.splitext(os.path.basename(schema_file))[0]
              for schema_file in schema_files]
docs: Return a list of content types in a repository.
  
      :param Repo repo:
          The git repository.
      :returns: list