class_docstr: Test the basic serializer and deserializer (i.e. using pickle),
  including metadata access.
class_docstr_tok: ["Test","the","basic","serializer","and","deserializer","(","i.e",".","using","pickle",")",",","including","metadata","access","."]
code: def test_renderer_encode_unicode_types(self):
      mime_types = ["image/svg+xml", "text/html", "text/json"]
      for mime in mime_types:
          info = {"mime_type": mime}
          encoded = Renderer.encode(
              ("Testing «ταБЬℓσ»: 1<2 & 4+1>3", info)
          )
          self.assertTrue(isinstance(encoded, bytes))
  
imports: from holoviews.element.comparison import ComparisonTestCase
  from holoviews.plotting import Renderer
label_desc: Use image node_id 1 for calling the TestRenderer obj's underlying member method code with example usage: obj.test_renderer_encode_unicode_types() without return types