code: def mkdir(self, target_folder):
          
          self.printv("Making directory: %s" % target_folder)
          self.k.key = re.sub(r"^/|/$", "", target_folder) + "/"
          self.k.set_contents_from_string('')
          self.k.close()
docs: Create a folder on S3.
  
          Examples
          --------
              >>> s3utils.mkdir("path/to/my_folder")
              Making directory: path/to/my_folder