code: def _write_fetcher(self, specification, specification_set):
          
          destination = "%s" % (self.output_directory)
          base_name = "%sFetcher" % specification.entity_name_plural
          filename = "vspk/%s%s.cs" % (self._class_prefix, base_name)
          override_content = self._extract_override_content(base_name)
  
          self.write(destination=destination,
                     filename=filename,
                     template_name="fetcher.cs.tpl",
                     specification=specification,
                     specification_set=specification_set,
                     class_prefix=self._class_prefix,
                     product_accronym=self._product_accronym,
                     override_content=override_content,
                     header=self.header_content,
                     name=self._name,
                     version_string=self._api_version_string,
                     package_name=self._package_name)
  
          return (filename, specification.entity_name_plural)
docs: Write fetcher