class_docstr: Test the OHE vector encoder 
docstr: Ensure binary strictly enforces binary typing 
docstr_tok: ["Ensure","binary","strictly","enforces","binary","typing"]
code: def test_check_only_binary(self):
      """Ensure binary strictly enforces binary typing"""
      data = ["apple", "apple", "orange", "banana", "apple", "orange"]
  
      enc = BinaryEncoder(handle_unknown="error")
      self.assertRaises(ValueError, enc.prepare, data)
  
file_path: lightwood/tests/unit_tests/encoder/categorical/test_binary.py
imports: import unittest
  import torch
  from torch import Tensor
  import numpy
  from lightwood.encoder.categorical.binary import BinaryEncoder
  from lightwood.helpers.constants import _UNCOMMON_WORD
label_desc: Use image node_id 2 for calling the TestBinary obj's underlying member method code with example usage: obj.test_check_only_binary() without return types