code: def test_module_exists_base_level_modules():
      assert module_exists("pytest")
      assert not module_exists("clearly_non_existing_module_name")
  
imports: import pytest
  from sacred.utils import PATHCHANGE, convert_to_nested_dict, get_by_dotted_path, is_prefix, iter_prefixes, iterate_flattened, iterate_flattened_separately, join_paths, recursive_update, set_by_dotted_path, get_inheritors, convert_camel_case_to_snake_case, apply_backspaces_and_linefeeds, module_exists, module_is_in_cache, get_package_version, parse_version, rel_path
label_desc: Use image node_id 15 for calling a global function with example usage: test_module_exists_base_level_modules() without return types