code: def test_varnames_keyword_only():
      # SyntaxError on Python 2, so we exec
      ns = {}
      exec(
          "def f1(x, *, y): pass\n"
          "def f2(x, *, y=3): pass\n"
          "def f3(x=1, *, y=3): pass\n",
          ns,
      )
  
      assert varnames(ns["f1"]) == (("x",), ())
      assert varnames(ns["f2"]) == (("x",), ())
      assert varnames(ns["f3"]) == ((), ("x",))
  
file_path: catboost/contrib/python/pluggy/py2/tests/test_helpers.py
imports: from pluggy.hooks import varnames
  from pluggy.manager import _formatdef
  import sys
  import pytest
label_desc: Use image node_id 4 for calling a global function with example usage: test_varnames_keyword_only() without return types