code: def test_formatdef():
      def function1():
          pass
  
      assert _formatdef(function1) == "function1()"
  
      def function2(arg1):
          pass
  
      assert _formatdef(function2) == "function2(arg1)"
  
      def function3(arg1, arg2="qwe"):
          pass
  
      assert _formatdef(function3) == "function3(arg1, arg2='qwe')"
  
      def function4(arg1, *args, **kwargs):
          pass
  
      assert _formatdef(function4) == "function4(arg1, *args, **kwargs)"
  
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 5 for calling a global function with example usage: test_formatdef() without return types