docs: def build(self):
          "Build your book"
          config = self.load_config()
          html_generator = HTMLGenerator(self.cwd, config)
          html_generator.build()
  
          if self.args.get('--generator', None):
              generator = self.args.get('--generator')
          else:
              generator = config.get('generator')
  
          if generator == 'calibre':
              EPUBClass = CalibreEPUBGenerator
              PDFClass = CalibrePDFGenerator
          elif generator == 'pandoc':
              EPUBClass = PandocEPUBGenerator
              PDFClass = PandocPDFGenerator
          else:
              raise ConfigurationError(
                  "Wrong configuration. Please check your config.json file.")
  
          # EPUB Generation
          epub_generator = EPUBClass(self.cwd, config, self.args)
          epub_generator.build()
  
          # Shall we proceed to the PDF?
          if config.get('pdf', False) or self.args['--with-pdf']:
              pdf_generator = PDFClass(self.cwd, config, self.args)
              pdf_generator.build()