code: def test_strlen(client):
      client.json().set("str", Path.root_path(), "foo")
      assert 3 == client.json().strlen("str", Path.root_path())
      client.json().strappend("str", "bar", Path.root_path())
      assert 6 == client.json().strlen("str", Path.root_path())
      assert 6 == client.json().strlen("str")
  
imports: import pytest
  import redis
  from redis import Redis, exceptions
  from redis.commands.json.decoders import decode_list, unstring
  from redis.commands.json.path import Path
  from .conftest import _get_client, assert_resp_response, skip_ifmodversion_lt
label_desc: Use image node_id 17 for calling a global function with example usage: test_strlen(client) without return types