code: def test_verify_biallelic(self):
      mt = hl.import_vcf(resource("sample2.vcf"))  # has multiallelics
      with self.assertRaises(hl.utils.HailUserError):
          hl.methods.misc.require_biallelic(mt, "")._force_count_rows()
  
imports: import unittest
  import hail
  from ..helpers import *
label_desc: Use image node_id 15 for calling the Tests obj's underlying member method code with example usage: obj.test_verify_biallelic() without return types