class_docstr: Test ParlaiParser.
class_docstr_tok: ["Test","ParlaiParser","."]
docstr: Test whether recommended args work for non-group.
docstr_tok: ["Test","whether","recommended","args","work","for","non-group","."]
code: def test_recommendations_single(self):
      """
      Test whether recommended args work for non-group.
      """
      parser = ParlaiParser(False, False)
      parser.add_argument(
          "-bs",
          "--batchsize",
          default=1,
          type=int,
          help="batch size for minibatch training schemes",
          recommended=1337,
      )
      parser.parse_args([])
      help_str = parser.format_help()
      assert "recommended:" in help_str
      assert "1337" in help_str
  
imports: import os
  import json
  import unittest
  from parlai.core.params import ParlaiParser
  import parlai.core.agents
  import parlai.utils.testing
label_desc: Use image node_id 4 for calling the TestParlaiParser obj's underlying member method code with example usage: obj.test_recommendations_single() without return types