code: def test_obv():
      """test OBC"""
  
      obv = TA.OBV(ohlc)
      talib_obv = talib.OBV(ohlc["close"], ohlc["volume"])
  
      # assert obv.values[-1] == talib_obv[-1]
      # assert -149123.0 == -148628.0
      pass
  
imports: import pytest
  import os
  import pandas
  from finta import TA
  import talib
label_desc: Use image node_id 20 for calling a global function with example usage: test_obv() without return types