code: def test_init(self):
      with self.assertRaises(AssertionError):
          MaskedBalancedBCELoss(reduction="any")
  
      with self.assertRaises(AssertionError):
          MaskedBalancedBCELoss(negative_ratio="a")
  
      with self.assertRaises(AssertionError):
          MaskedBalancedBCELoss(eps="a")
  
      with self.assertRaises(AssertionError):
          MaskedBalancedBCELoss(fallback_negative_num="a")
  
imports: from unittest import TestCase
  import torch
  from mmocr.models.common.losses import MaskedBalancedBCELoss, MaskedBalancedBCEWithLogitsLoss, MaskedBCELoss, MaskedBCEWithLogitsLoss
label_desc: Use image node_id 2 for calling the TestMaskedBalancedBCELoss obj's underlying member method code with example usage: obj.test_init() without return types