code: def test_non_ascii_key(self):
      testjson = (
          b'[{"\xc3\x9cnic\xc3\xb8de":0,"sub":{"A":1, "B":2}},'
          b'{"\xc3\x9cnic\xc3\xb8de":1,"sub":{"A":3, "B":4}}]'
      ).decode("utf8")
  
      testdata = {
          b"\xc3\x9cnic\xc3\xb8de".decode("utf8"): [0, 1],
          "sub.A": [1, 3],
          "sub.B": [2, 4],
      }
      expected = DataFrame(testdata)
  
      result = json_normalize(json.loads(testjson))
      tm.assert_frame_equal(result, expected)
  
imports: import json
  import numpy
  import pytest
  from pandas import DataFrame, Index, Series, json_normalize
  import pandas._testing
  from pandas.io.json._normalize import nested_to_record
label_desc: Use image node_id 16 for calling the TestJSONNormalize obj's underlying member method code with example usage: obj.test_non_ascii_key() without return types