code: def test_hadoop_ls_simple(self):
      with hl.TemporaryDirectory() as dirname:
          with hl.current_backend().fs.open(
              dirname + "/a", "w"
          ) as fobj:
              fobj.write("hello world")
          dirname = normalize_path(dirname)
  
          results = hl.hadoop_ls(dirname + "/[a]")
          assert len(results) == 1
          assert results[0]["path"] == dirname + "/a"
  
imports: import json
  import unittest
  import hail
  from hail.utils import *
  from hail.utils.misc import escape_str, escape_id
  from hail.utils.java import FatalError
  from hail.utils.linkedlist import LinkedList
  from ..helpers import *
label_desc: Use image node_id 10 for calling the Tests obj's underlying member method code with example usage: obj.test_hadoop_ls_simple() without return types