linted a few modules, added a check that the language_code exists when calling Transcriber.transcribe, made that method non-abstract to do so. Added a test for this. Extracted a few things to fixtures.

tatt/tests/test_amazon.py

@@ -1,23 +1,30 @@
 from unittest import mock
+from pytest import raises, fixture
 
 from tatt.vendors.amazon import Transcriber
 
 
+@fixture
+def media_filepath():
+    return "/Users/zev/tester.mp3"
 
-def test_transcriber_instantiate():
+
-    filepath = '/Users/zev/tester.mp3'
+@fixture
-    t = Transcriber(filepath)
+def transcriber_instance(media_filepath):
-    assert str(t.filepath) == filepath
+    return Transcriber(media_filepath)
-    assert t.basename == 'tester.mp3'
+
-    assert t.media_file_uri == (
+
-        f'https://s3-us-east-1.amazonaws.com/tatt-media-amazon/tester.mp3'
+def test_transcriber_instance(media_filepath, transcriber_instance):
+    assert str(transcriber_instance.filepath) == media_filepath
+    assert transcriber_instance.basename == "tester.mp3"
+    assert transcriber_instance.media_file_uri == (
+        f"https://s3-us-east-1.amazonaws.com/tatt-media-amazon/tester.mp3"
     )
 
 
-@mock.patch('tatt.vendors.amazon.tr.get_transcription_job')
+@mock.patch("tatt.vendors.amazon.tr.get_transcription_job")
 def test_transcriber_retrieve(get_transcription_job):
-    filepath = '/Users/zev/tester.mp3'
+    job_name = "4db6808e-a7e8-4d8d-a1b7-753ab97094dc"
-    job_name = '4db6808e-a7e8-4d8d-a1b7-753ab97094dc'
     t = Transcriber.retrieve_transcript(job_name)
     get_transcription_job.assert_called_with(TranscriptionJobName=job_name)
 
@@ -29,9 +36,40 @@ def test_transcriber_get_transcription_jobs():
 
 def test_transcriber_retrieve_transcript():
     jobs = Transcriber.get_transcription_jobs()
+    assert jobs
     for j in jobs:
-        if j['status'].lower() == 'completed':
+        if j["status"].lower() == "completed":
-            to_get = j['name']
+            to_get = j["name"]
             break
     transcript = Transcriber.retrieve_transcript(to_get)
-    assert transcript == {'jobName': 'abcd.mp3', 'accountId': '416321668733', 'results': {'transcripts': [{'transcript': 'Hello there.'}], 'items': [{'start_time': '0.0', 'end_time': '0.35', 'alternatives': [{'confidence': '0.8303', 'content': 'Hello'}], 'type': 'pronunciation'}, {'start_time': '0.35', 'end_time': '0.76', 'alternatives': [{'confidence': '1.0000', 'content': 'there'}], 'type': 'pronunciation'}, {'alternatives': [{'confidence': None, 'content': '.'}], 'type': 'punctuation'}]}, 'status': 'COMPLETED'}
+    assert transcript == {
+        "jobName": "abcd.mp3",
+        "accountId": "416321668733",
+        "results": {
+            "transcripts": [{"transcript": "Hello there."}],
+            "items": [
+                {
+                    "start_time": "0.0",
+                    "end_time": "0.35",
+                    "alternatives": [{"confidence": "0.8303", "content": "Hello"}],
+                    "type": "pronunciation",
+                },
+                {
+                    "start_time": "0.35",
+                    "end_time": "0.76",
+                    "alternatives": [{"confidence": "1.0000", "content": "there"}],
+                    "type": "pronunciation",
+                },
+                {
+                    "alternatives": [{"confidence": None, "content": "."}],
+                    "type": "punctuation",
+                },
+            ],
+        },
+        "status": "COMPLETED",
+    }
+
+
+def test_transcribe_with_nonexistent_language_code(transcriber_instance):
+    with raises(KeyError):
+        transcriber_instance.transcribe(language_code="pretend-lang")

tatt/tests/test_vendors.py

@@ -3,6 +3,6 @@ from tatt.vendors import SERVICES
 
 def test_services():
     for service in SERVICES.values():
-        assert hasattr(service, 'Transcriber')
+        assert hasattr(service, "Transcriber")
-        assert hasattr(service, 'NAME')
+        assert hasattr(service, "NAME")
-        assert hasattr(service.Transcriber, 'cost_per_15_seconds')
+        assert hasattr(service.Transcriber, "cost_per_15_seconds")

tatt/vendors/__init__.py

@@ -1,7 +1,3 @@
 from tatt.vendors import amazon, google
 
-SERVICES = {
+SERVICES = {"amazon": amazon, "google": google}
-        'amazon': amazon,
-        'google': google,
-        }
-

tatt/vendors/amazon.py

@@ -11,7 +11,7 @@ from tatt import config
 from tatt import exceptions
 from .vendor import TranscriberBaseClass
 
-NAME = 'amazon'
+NAME = "amazon"
 BUCKET_NAME_MEDIA = config.BUCKET_NAME_FMTR_MEDIA.format(NAME)
 BUCKET_NAME_TRANSCRIPT = config.BUCKET_NAME_FMTR_TRANSCRIPT.format(NAME)
 TRANSCRIPT_TYPE = dict
@@ -19,28 +19,35 @@ TRANSCRIPT_TYPE = dict
 
 def _check_for_config() -> bool:
     return (
-        config.AWS_CONFIG_FILEPATH.exists()
+        config.AWS_CONFIG_FILEPATH.exists() and config.AWS_CREDENTIALS_FILEPATH.exists()
-        and config.AWS_CREDENTIALS_FILEPATH.exists()
     )
 
 
-
 class Transcriber(TranscriberBaseClass):
 
     name = NAME
-    cost_per_15_seconds = .024 / 4
+    cost_per_15_seconds = 0.024 / 4
-    bucket_names = {'media': BUCKET_NAME_MEDIA,
+    bucket_names = {"media": BUCKET_NAME_MEDIA, "transcript": BUCKET_NAME_TRANSCRIPT}
-                    'transcript': BUCKET_NAME_TRANSCRIPT}
 
     no_config_error_message = 'please run "aws configure" first'
     transcript_type = TRANSCRIPT_TYPE
     # https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/transcribe.html
-    _language_list = ['en-US', 'es-US', 'en-AU', 'fr-CA', 'en-GB', 'de-DE', 
+    _language_list = [
-                     'pt-BR', 'fr-FR', 'it-IT', 'ko-KR']
+        "en-US",
+        "es-US",
+        "en-AU",
+        "fr-CA",
+        "en-GB",
+        "de-DE",
+        "pt-BR",
+        "fr-FR",
+        "it-IT",
+        "ko-KR",
+    ]
 
     if _check_for_config():
-        tr = boto3.client('transcribe')
+        tr = boto3.client("transcribe")
-        s3 = boto3.resource('s3')
+        s3 = boto3.resource("s3")
 
     def __init__(self, filepath):
         super().__init__(filepath)
@@ -75,98 +82,96 @@ class Transcriber(TranscriberBaseClass):
         cls.s3.create_bucket(Bucket=bucket_name)
 
     def transcribe(self, **kwargs) -> str:
+        super().transcribe(**kwargs)
         self._upload_file()
         try:
             return self._request_transcription(**kwargs)
         except self.tr.exceptions.ConflictException:
             raise exceptions.AlreadyExistsError(
-                f'{self.basename} already exists on {NAME}')
+                f"{self.basename} already exists on {NAME}"
+            )
 
     def _upload_file(self):
-        self.s3.Bucket(self.bucket_names['media']).upload_file(
+        self.s3.Bucket(self.bucket_names["media"]).upload_file(
-                str(self.filepath),
+            str(self.filepath), self.basename
-                self.basename)
+        )
 
     def _request_transcription(
-            self, 
+        self, language_code="en-US", num_speakers=2, enable_speaker_diarization=True
-            language_code='en-US', 
-            num_speakers=2,
-            enable_speaker_diarization=True,
     ) -> str:
         job_name = self.basename
 
         kwargs = dict(
             TranscriptionJobName=job_name,
             LanguageCode=language_code,
-                MediaFormat=self.basename.split('.')[-1].lower(),
+            MediaFormat=self.basename.split(".")[-1].lower(),
-                Media={
+            Media={"MediaFileUri": self.media_file_uri},
-                    'MediaFileUri': self.media_file_uri
+            OutputBucketName=self.bucket_names["transcript"],
-                    },
-                OutputBucketName=self.bucket_names['transcript']
         )
 
         if enable_speaker_diarization:
-            kwargs.update(dict(
+            kwargs.update(
+                dict(
                     Settings={
-                    'ShowSpeakerLabels': True,
+                        "ShowSpeakerLabels": True,
-                    'MaxSpeakerLabels': num_speakers,
+                        "MaxSpeakerLabels": num_speakers,
                     }
-                    ))
+                )
+            )
 
         self.tr.start_transcription_job(**kwargs)
         return job_name
 
     @classmethod
     def get_transcription_jobs(
-            cls,
+        cls, status: str = None, job_name_query: str = None
-            status:str = None, 
-            job_name_query:str = None,
     ) -> List[dict]:
 
-        kwargs = {'MaxResults': 100}
+        kwargs = {"MaxResults": 100}
 
         if status is not None:
-            kwargs['Status'] = status.upper()
+            kwargs["Status"] = status.upper()
         if job_name_query is not None:
-            kwargs['JobNameContains'] = job_name_query
+            kwargs["JobNameContains"] = job_name_query
 
         jobs_data = cls.tr.list_transcription_jobs(**kwargs)
-        key = 'TranscriptionJobSummaries'
+        key = "TranscriptionJobSummaries"
 
         jobs = cls.homogenize_transcription_job_data(jobs_data[key])
 
-        while jobs_data.get('NextToken'):
+        while jobs_data.get("NextToken"):
-            token = jobs_data['NextToken']
+            token = jobs_data["NextToken"]
             jobs_data = cls.tr.list_transcription_jobs(NextToken=token)
             jobs += cls.homogenize_transcription_job_data(jobs_data[key])
 
         return jobs
 
     @classmethod
-    def retrieve_transcript(cls, transcription_job_name: str
+    def retrieve_transcript(cls, transcription_job_name: str) -> TRANSCRIPT_TYPE:
-            ) -> TRANSCRIPT_TYPE:
+        job = cls.tr.get_transcription_job(TranscriptionJobName=transcription_job_name)[
-        job = cls.tr.get_transcription_job(
+            "TranscriptionJob"
-            TranscriptionJobName=transcription_job_name
+        ]
-        )['TranscriptionJob']
 
-        if not job['TranscriptionJobStatus'] == 'COMPLETED':
+        if not job["TranscriptionJobStatus"] == "COMPLETED":
             return
 
-        transcript_file_uri = job['Transcript']['TranscriptFileUri']
+        transcript_file_uri = job["Transcript"]["TranscriptFileUri"]
         transcript_path = transcript_file_uri.split("amazonaws.com/", 1)[1]
 
-        transcript_bucket = transcript_path.split('/', 1)[0]
+        transcript_bucket = transcript_path.split("/", 1)[0]
-        transcript_key = transcript_path.split('/', 1)[1]
+        transcript_key = transcript_path.split("/", 1)[1]
 
         s3_object = cls.s3.Object(transcript_bucket, transcript_key).get()
-        transcript_json = s3_object['Body'].read().decode('utf-8')
+        transcript_json = s3_object["Body"].read().decode("utf-8")
         return json.loads(transcript_json)
 
     @staticmethod
     def homogenize_transcription_job_data(transcription_job_data):
-        return [{
+        return [
-                    'created': jd['CreationTime'],
+            {
-                    'name': jd['TranscriptionJobName'],
+                "created": jd["CreationTime"],
-                    'status': jd['TranscriptionJobStatus']
+                "name": jd["TranscriptionJobName"],
+                "status": jd["TranscriptionJobStatus"],
             }
-                for jd in transcription_job_data]
+            for jd in transcription_job_data
+        ]

tatt/vendors/google.py

@@ -17,46 +17,150 @@ from google.cloud import (
 from tatt import exceptions, helpers, config as config_mod
 from .vendor import TranscriberBaseClass
 
-NAME = 'google'
+NAME = "google"
-BUCKET_NAME_TRANSCRIPT = config_mod.BUCKET_NAME_FMTR_TRANSCRIPT_GOOGLE.format(
+BUCKET_NAME_TRANSCRIPT = config_mod.BUCKET_NAME_FMTR_TRANSCRIPT_GOOGLE.format("goog")
-        'goog')
 TRANSCRIPT_TYPE = str
 
 
 def _check_for_config():
-    return os.getenv('GOOGLE_APPLICATION_CREDENTIALS') is not None
+    return os.getenv("GOOGLE_APPLICATION_CREDENTIALS") is not None
 
 
 class Transcriber(TranscriberBaseClass):
 
     name = NAME
-    SUPPORTED_FORMATS = ['flac']
+    SUPPORTED_FORMATS = ["flac"]
-    cost_per_15_seconds = [.004, .006, .009]
+    cost_per_15_seconds = [0.004, 0.006, 0.009]
     no_config_error_message = (
-            'Please sign up for the Google Speech-to-Text API '
+        "Please sign up for the Google Speech-to-Text API "
-            'and put the path to your credentials in an '
+        "and put the path to your credentials in an "
         'environment variable "GOOGLE_APPLICATION_CREDENTIALS"'
     )
     transcript_type = TRANSCRIPT_TYPE
     # https://cloud.google.com/speech-to-text/docs/languages
     # Array.from(document.querySelector('.devsite-table-wrapper').querySelectorAll('table tr')).slice(1).map(row => row.children[1].innerText)
     _language_list = [
-        'af-ZA', 'am-ET', 'hy-AM', 'az-AZ', 'id-ID', 'ms-MY',
+        "af-ZA",
-        'bn-BD', 'bn-IN', 'ca-ES', 'cs-CZ', 'da-DK', 'de-DE', 'en-AU', 'en-CA',
+        "am-ET",
-        'en-GH', 'en-GB', 'en-IN', 'en-IE', 'en-KE', 'en-NZ', 'en-NG', 'en-PH',
+        "hy-AM",
-        'en-SG', 'en-ZA', 'en-TZ', 'en-US', 'es-AR', 'es-BO', 'es-CL', 'es-CO',
+        "az-AZ",
-        'es-CR', 'es-EC', 'es-SV', 'es-ES', 'es-US', 'es-GT', 'es-HN', 'es-MX',
+        "id-ID",
-        'es-NI', 'es-PA', 'es-PY', 'es-PE', 'es-PR', 'es-DO', 'es-UY', 'es-VE',
+        "ms-MY",
-        'eu-ES', 'fil-PH', 'fr-CA', 'fr-FR', 'gl-ES', 'ka-GE', 'gu-IN', 'hr-HR',
+        "bn-BD",
-        'zu-ZA', 'is-IS', 'it-IT', 'jv-ID', 'kn-IN', 'km-KH', 'lo-LA', 'lv-LV',
+        "bn-IN",
-        'lt-LT', 'hu-HU', 'ml-IN', 'mr-IN', 'nl-NL', 'ne-NP', 'nb-NO', 'pl-PL',
+        "ca-ES",
-        'pt-BR', 'pt-PT', 'ro-RO', 'si-LK', 'sk-SK', 'sl-SI', 'su-ID', 'sw-TZ',
+        "cs-CZ",
-        'sw-KE', 'fi-FI', 'sv-SE', 'ta-IN', 'ta-SG', 'ta-LK', 'ta-MY', 'te-IN',
+        "da-DK",
-        'vi-VN', 'tr-TR', 'ur-PK', 'ur-IN', 'el-GR', 'bg-BG', 'ru-RU', 'sr-RS',
+        "de-DE",
-        'uk-UA', 'he-IL', 'ar-IL', 'ar-JO', 'ar-AE', 'ar-BH', 'ar-DZ', 'ar-SA',
+        "en-AU",
-        'ar-IQ', 'ar-KW', 'ar-MA', 'ar-TN', 'ar-OM', 'ar-PS', 'ar-QA', 'ar-LB',
+        "en-CA",
-        'ar-EG', 'fa-IR', 'hi-IN', 'th-TH', 'ko-KR', 'zh-TW', 'yue-Hant-HK',
+        "en-GH",
-        'ja-JP', 'zh-HK', 'zh']
+        "en-GB",
+        "en-IN",
+        "en-IE",
+        "en-KE",
+        "en-NZ",
+        "en-NG",
+        "en-PH",
+        "en-SG",
+        "en-ZA",
+        "en-TZ",
+        "en-US",
+        "es-AR",
+        "es-BO",
+        "es-CL",
+        "es-CO",
+        "es-CR",
+        "es-EC",
+        "es-SV",
+        "es-ES",
+        "es-US",
+        "es-GT",
+        "es-HN",
+        "es-MX",
+        "es-NI",
+        "es-PA",
+        "es-PY",
+        "es-PE",
+        "es-PR",
+        "es-DO",
+        "es-UY",
+        "es-VE",
+        "eu-ES",
+        "fil-PH",
+        "fr-CA",
+        "fr-FR",
+        "gl-ES",
+        "ka-GE",
+        "gu-IN",
+        "hr-HR",
+        "zu-ZA",
+        "is-IS",
+        "it-IT",
+        "jv-ID",
+        "kn-IN",
+        "km-KH",
+        "lo-LA",
+        "lv-LV",
+        "lt-LT",
+        "hu-HU",
+        "ml-IN",
+        "mr-IN",
+        "nl-NL",
+        "ne-NP",
+        "nb-NO",
+        "pl-PL",
+        "pt-BR",
+        "pt-PT",
+        "ro-RO",
+        "si-LK",
+        "sk-SK",
+        "sl-SI",
+        "su-ID",
+        "sw-TZ",
+        "sw-KE",
+        "fi-FI",
+        "sv-SE",
+        "ta-IN",
+        "ta-SG",
+        "ta-LK",
+        "ta-MY",
+        "te-IN",
+        "vi-VN",
+        "tr-TR",
+        "ur-PK",
+        "ur-IN",
+        "el-GR",
+        "bg-BG",
+        "ru-RU",
+        "sr-RS",
+        "uk-UA",
+        "he-IL",
+        "ar-IL",
+        "ar-JO",
+        "ar-AE",
+        "ar-BH",
+        "ar-DZ",
+        "ar-SA",
+        "ar-IQ",
+        "ar-KW",
+        "ar-MA",
+        "ar-TN",
+        "ar-OM",
+        "ar-PS",
+        "ar-QA",
+        "ar-LB",
+        "ar-EG",
+        "fa-IR",
+        "hi-IN",
+        "th-TH",
+        "ko-KR",
+        "zh-TW",
+        "yue-Hant-HK",
+        "ja-JP",
+        "zh-HK",
+        "zh",
+    ]
 
     if _check_for_config():
         speech_client = speech.SpeechClient()
@@ -69,10 +173,11 @@ class Transcriber(TranscriberBaseClass):
     @classmethod
     def _setup(cls):
         super()._setup()
-        if not shutil.which('gsutil'):
+        if not shutil.which("gsutil"):
             raise exceptions.DependencyRequired(
-                'Please install gcloud using the steps here:'
+                "Please install gcloud using the steps here:"
-                'https://cloud.google.com/storage/docs/gsutil_install')
+                "https://cloud.google.com/storage/docs/gsutil_install"
+            )
 
         cls._make_bucket_if_doesnt_exist(BUCKET_NAME_TRANSCRIPT)
 
@@ -84,13 +189,13 @@ class Transcriber(TranscriberBaseClass):
             # this might fail if a bucket by the name exists *anywhere* on GCS?
             return
         else:
-            print('made Google Cloud Storage Bucket for transcripts')
+            print("made Google Cloud Storage Bucket for transcripts")
 
     def convert_file_format_if_needed(self):
         if self.file_format not in self.SUPPORTED_FORMATS:
-            if not shutil.which('ffmpeg'):
+            if not shutil.which("ffmpeg"):
-                raise exceptions.DependencyRequired('please install ffmpeg')
+                raise exceptions.DependencyRequired("please install ffmpeg")
-            self.filepath = helpers.convert_file(self.filepath, 'flac')
+            self.filepath = helpers.convert_file(self.filepath, "flac")
 
     @property
     def file_format(self):
@@ -111,31 +216,31 @@ class Transcriber(TranscriberBaseClass):
 
     def _check_if_transcript_exists(self, transcript_name=None):
         return storage.Blob(
-                    bucket=self.transcript_bucket, 
+            bucket=self.transcript_bucket, name=transcript_name or self.basename
-                    name=transcript_name or self.basename
         ).exists(self.storage_client)
 
     def _request_transcription(
         self,
-            language_code='en-US',
+        language_code="en-US",
         enable_automatic_punctuation=True,
         enable_speaker_diarization=True,
         num_speakers=2,
-            model='phone_call',
+        model="phone_call",
         use_enhanced=True,
     ) -> str:
         """Returns the job_name"""
         if self._check_if_transcript_exists():
             raise exceptions.AlreadyExistsError(
-                f'{self.basename} already exists on {NAME}')
+                f"{self.basename} already exists on {NAME}"
+            )
         num_audio_channels = helpers.get_num_audio_channels(self.filepath)
         sample_rate = helpers.get_sample_rate(self.filepath)
 
-        with io.open(self.filepath, 'rb') as audio_file:
+        with io.open(self.filepath, "rb") as audio_file:
             content = audio_file.read()
             audio = speech.types.RecognitionAudio(content=content)
 
-        if language_code != 'en-US':
+        if language_code != "en-US":
             model = None
 
         config = speech.types.RecognitionConfig(
@@ -153,37 +258,35 @@ class Transcriber(TranscriberBaseClass):
             use_enhanced=use_enhanced,
         )
 
-        self.operation = self.speech_client.long_running_recognize(config, 
+        self.operation = self.speech_client.long_running_recognize(config, audio)
-                                                                   audio)
 
-        print('transcribing...')
+        print("transcribing...")
         while not self.operation.done():
             sleep(1)
-            print('.')
+            print(".")
 
         result_list = []
 
         for result in self.operation.result().results:
             result_list.append(str(result))
 
-        print('saving transcript')
+        print("saving transcript")
-        transcript_path = '/tmp/transcript.txt'
+        transcript_path = "/tmp/transcript.txt"
-        with open(transcript_path, 'w') as fout:
+        with open(transcript_path, "w") as fout:
-            fout.write('\n'.join(result_list))
+            fout.write("\n".join(result_list))
-        print('uploading transcript')
+        print("uploading transcript")
         self.upload_file(BUCKET_NAME_TRANSCRIPT, transcript_path)
         os.remove(transcript_path)
 
         return self.basename
 
     @classmethod
-    def retrieve_transcript(cls, transcription_job_name: str
+    def retrieve_transcript(cls, transcription_job_name: str) -> TRANSCRIPT_TYPE:
-            ) -> TRANSCRIPT_TYPE:
         """Get transcript from BUCKET_NAME_TRANSCRIPT"""
         if not cls._check_if_transcript_exists(
-                cls,
+            cls, transcript_name=transcription_job_name
-                transcript_name=transcription_job_name):
+        ):
-            raise exceptions.DoesntExistError('no such transcript!')
+            raise exceptions.DoesntExistError("no such transcript!")
         blob = cls.transcript_bucket.blob(transcription_job_name)
         f = tempfile.NamedTemporaryFile(delete=False)
         f.close()
@@ -202,7 +305,7 @@ class Transcriber(TranscriberBaseClass):
     @classmethod
     def get_transcription_jobs(cls, job_name_query=None, status=None) -> List[dict]:
 
-        if status and status.lower() != 'completed':
+        if status and status.lower() != "completed":
             return []
 
         jobs = []
@@ -210,6 +313,6 @@ class Transcriber(TranscriberBaseClass):
         for t in cls.transcript_bucket.list_blobs():
             if job_name_query is not None and t.name != job_name_query:
                 continue
-            jobs.append({'name': t.name, 'status': 'COMPLETED'})
+            jobs.append({"name": t.name, "status": "COMPLETED"})
 
         return jobs

tatt/vendors/vendor.py

@@ -12,8 +12,8 @@ class TranscriberBaseClass:
 
     def __init__(self, filepath):
         self._setup()
-        if ' ' in filepath:
+        if " " in filepath:
-            raise exceptions.FormatError('Please don\'t put any spaces in the filename.')
+            raise exceptions.FormatError("Please don't put any spaces in the filename.")
         self.filepath = PurePath(filepath)
         self.basename = str(os.path.basename(self.filepath))
 
@@ -52,14 +52,14 @@ class TranscriberBaseClass:
     def check_for_config(cls) -> bool:
         pass
 
-    @abc.abstractmethod
+    def transcribe(self, **kwargs) -> str:
-    def transcribe(self) -> str:
         """
         This should do any required logic, 
         then call self._request_transcription.
         It should return the job_name.
         """
-        pass
+        if kwargs["language_code"] not in self.language_list():
+            raise KeyError(f"No such language code {kwargs['language_code']}")
 
     @abc.abstractmethod
     def _request_transcription(self) -> str:
@@ -72,12 +72,10 @@ class TranscriberBaseClass:
 
     @classmethod
     @abc.abstractmethod
-    def retrieve_transcript(cls, transcription_job_name: str
+    def retrieve_transcript(cls, transcription_job_name: str) -> Union[str, dict]:
-            ) -> Union[str, dict]:
         pass
 
     @classmethod
     @abc.abstractmethod
     def get_transcription_jobs() -> List[dict]:
         pass
-