code: def _get_snippet_ctime(self, snip_name):
          
          if snip_name not in self.snip_ctimes:
              snippet = yaml_snippet_loader.YamlSnippetLoader.get_snippet_by_name(snip_name)
              self.snip_ctimes[snip_name] = os.path.getctime(snippet.path)
          return self.snip_ctimes[snip_name]
docs: Returns and remembers (during this DevAssistant invocation) last ctime of given
          snippet.
  
          Calling ctime costs lost of time and some snippets, like common_args, are used widely,
          so we don't want to call ctime bazillion times on them during one invocation.
  
          Args:
              snip_name: name of snippet to get ctime for
          Returns:
              ctime of the snippet