code: def test_au_n_enc_mt(self):
      g = graphistry.bind()
      au = ArrowUploader()
      assert au.g_to_node_encodings(g) == {"bindings": {}}
  
imports: import graphistry, mock, pandas, pytest, unittest
  from graphistry import ArrowUploader
  from graphistry.pygraphistry import PyGraphistry
label_desc: Use image node_id 3 for calling the TestArrowUploader_Core obj's underlying member method code with example usage: obj.test_au_n_enc_mt() without return types