code: def check(self):
          
          if not isinstance(self.parsed_yaml, dict):
              msg = 'In {0}:\n'.format(self.sourcefile)
              msg += 'Assistants and snippets must be Yaml mappings, not "{0}"!'.\
                  format(self.parsed_yaml)
              raise exceptions.YamlTypeError(msg)
          self._check_fullname(self.sourcefile)
          self._check_description(self.sourcefile)
          self._check_section_names(self.sourcefile)
          self._check_project_type(self.sourcefile)
          self._check_args(self.sourcefile)
          self._check_files(self.sourcefile)
          self._check_dependencies(self.sourcefile)
          self._check_run(self.sourcefile)
docs: Checks whether loaded yaml is well-formed according to syntax defined for
          version 0.9.0 and later.
  
          Raises:
              YamlError: (containing a meaningful message) when the loaded Yaml
                  is not well formed