There are more AWS SDK examples available in the [AWS Doc SDK Examples](https://github.com/awsdocs/aws-doc-sdk-examples) GitHub repo.

# Amazon Polly examples using SDK for Python (Boto3)
<a name="python_3_polly_code_examples"></a>

The following code examples show you how to perform actions and implement common scenarios by using the AWS SDK for Python (Boto3) with Amazon Polly.

*Actions* are code excerpts from larger programs and must be run in context. While actions show you how to call individual service functions, you can see actions in context in their related scenarios.

*Scenarios* are code examples that show you how to accomplish specific tasks by calling multiple functions within a service or combined with other AWS services.

Each example includes a link to the complete source code, where you can find instructions on how to set up and run the code in context.

**Topics**
+ [Actions](#actions)
+ [Scenarios](#scenarios)

## Actions
<a name="actions"></a>

### `DescribeVoices`
<a name="polly_DescribeVoices_python_3_topic"></a>

The following code example shows how to use `DescribeVoices`.

**SDK for Python (Boto3)**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/polly#code-examples). 

```
class PollyWrapper:
    """Encapsulates Amazon Polly functions."""

    def __init__(self, polly_client, s3_resource):
        """
        :param polly_client: A Boto3 Amazon Polly client.
        :param s3_resource: A Boto3 Amazon Simple Storage Service (Amazon S3) resource.
        """
        self.polly_client = polly_client
        self.s3_resource = s3_resource
        self.voice_metadata = None


    def describe_voices(self):
        """
        Gets metadata about available voices.

        :return: The list of voice metadata.
        """
        try:
            response = self.polly_client.describe_voices()
            self.voice_metadata = response["Voices"]
            logger.info("Got metadata about %s voices.", len(self.voice_metadata))
        except ClientError:
            logger.exception("Couldn't get voice metadata.")
            raise
        else:
            return self.voice_metadata
```
+  For API details, see [DescribeVoices](https://docs.aws.amazon.com/goto/boto3/polly-2016-06-10/DescribeVoices) in *AWS SDK for Python (Boto3) API Reference*. 

### `GetLexicon`
<a name="polly_GetLexicon_python_3_topic"></a>

The following code example shows how to use `GetLexicon`.

**SDK for Python (Boto3)**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/polly#code-examples). 

```
class PollyWrapper:
    """Encapsulates Amazon Polly functions."""

    def __init__(self, polly_client, s3_resource):
        """
        :param polly_client: A Boto3 Amazon Polly client.
        :param s3_resource: A Boto3 Amazon Simple Storage Service (Amazon S3) resource.
        """
        self.polly_client = polly_client
        self.s3_resource = s3_resource
        self.voice_metadata = None


    def get_lexicon(self, name):
        """
        Gets metadata and contents of an existing lexicon.

        :param name: The name of the lexicon to retrieve.
        :return: The retrieved lexicon.
        """
        try:
            response = self.polly_client.get_lexicon(Name=name)
            logger.info("Got lexicon %s.", name)
        except ClientError:
            logger.exception("Couldn't get lexicon %s.", name)
            raise
        else:
            return response
```
+  For API details, see [GetLexicon](https://docs.aws.amazon.com/goto/boto3/polly-2016-06-10/GetLexicon) in *AWS SDK for Python (Boto3) API Reference*. 

### `GetSpeechSynthesisTask`
<a name="polly_GetSpeechSynthesisTask_python_3_topic"></a>

The following code example shows how to use `GetSpeechSynthesisTask`.

**SDK for Python (Boto3)**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/polly#code-examples). 

```
class PollyWrapper:
    """Encapsulates Amazon Polly functions."""

    def __init__(self, polly_client, s3_resource):
        """
        :param polly_client: A Boto3 Amazon Polly client.
        :param s3_resource: A Boto3 Amazon Simple Storage Service (Amazon S3) resource.
        """
        self.polly_client = polly_client
        self.s3_resource = s3_resource
        self.voice_metadata = None


    def get_speech_synthesis_task(self, task_id):
        """
        Gets metadata about an asynchronous speech synthesis task, such as its status.

        :param task_id: The ID of the task to retrieve.
        :return: Metadata about the task.
        """
        try:
            response = self.polly_client.get_speech_synthesis_task(TaskId=task_id)
            task = response["SynthesisTask"]
            logger.info("Got synthesis task. Status is %s.", task["TaskStatus"])
        except ClientError:
            logger.exception("Couldn't get synthesis task %s.", task_id)
            raise
        else:
            return task
```
+  For API details, see [GetSpeechSynthesisTask](https://docs.aws.amazon.com/goto/boto3/polly-2016-06-10/GetSpeechSynthesisTask) in *AWS SDK for Python (Boto3) API Reference*. 

### `ListLexicons`
<a name="polly_ListLexicons_python_3_topic"></a>

The following code example shows how to use `ListLexicons`.

**SDK for Python (Boto3)**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/polly#code-examples). 

```
class PollyWrapper:
    """Encapsulates Amazon Polly functions."""

    def __init__(self, polly_client, s3_resource):
        """
        :param polly_client: A Boto3 Amazon Polly client.
        :param s3_resource: A Boto3 Amazon Simple Storage Service (Amazon S3) resource.
        """
        self.polly_client = polly_client
        self.s3_resource = s3_resource
        self.voice_metadata = None


    def list_lexicons(self):
        """
        Lists lexicons in the current account.

        :return: The list of lexicons.
        """
        try:
            response = self.polly_client.list_lexicons()
            lexicons = response["Lexicons"]
            logger.info("Got %s lexicons.", len(lexicons))
        except ClientError:
            logger.exception(
                "Couldn't get  %s.",
            )
            raise
        else:
            return lexicons
```
+  For API details, see [ListLexicons](https://docs.aws.amazon.com/goto/boto3/polly-2016-06-10/ListLexicons) in *AWS SDK for Python (Boto3) API Reference*. 

### `PutLexicon`
<a name="polly_PutLexicon_python_3_topic"></a>

The following code example shows how to use `PutLexicon`.

**SDK for Python (Boto3)**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/polly#code-examples). 

```
class PollyWrapper:
    """Encapsulates Amazon Polly functions."""

    def __init__(self, polly_client, s3_resource):
        """
        :param polly_client: A Boto3 Amazon Polly client.
        :param s3_resource: A Boto3 Amazon Simple Storage Service (Amazon S3) resource.
        """
        self.polly_client = polly_client
        self.s3_resource = s3_resource
        self.voice_metadata = None


    def create_lexicon(self, name, content):
        """
        Creates a lexicon with the specified content. A lexicon contains custom
        pronunciations.

        :param name: The name of the lexicon.
        :param content: The content of the lexicon.
        """
        try:
            self.polly_client.put_lexicon(Name=name, Content=content)
            logger.info("Created lexicon %s.", name)
        except ClientError:
            logger.exception("Couldn't create lexicon %s.")
            raise
```
+  For API details, see [PutLexicon](https://docs.aws.amazon.com/goto/boto3/polly-2016-06-10/PutLexicon) in *AWS SDK for Python (Boto3) API Reference*. 

### `StartSpeechSynthesisTask`
<a name="polly_StartSpeechSynthesisTask_python_3_topic"></a>

The following code example shows how to use `StartSpeechSynthesisTask`.

**SDK for Python (Boto3)**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/polly#code-examples). 

```
class PollyWrapper:
    """Encapsulates Amazon Polly functions."""

    def __init__(self, polly_client, s3_resource):
        """
        :param polly_client: A Boto3 Amazon Polly client.
        :param s3_resource: A Boto3 Amazon Simple Storage Service (Amazon S3) resource.
        """
        self.polly_client = polly_client
        self.s3_resource = s3_resource
        self.voice_metadata = None


    def do_synthesis_task(
        self,
        text,
        engine,
        voice,
        audio_format,
        s3_bucket,
        lang_code=None,
        include_visemes=False,
        wait_callback=None,
    ):
        """
        Start an asynchronous task to synthesize speech or speech marks, wait for
        the task to complete, retrieve the output from Amazon S3, and return the
        data.

        An asynchronous task is required when the text is too long for near-real time
        synthesis.

        :param text: The text to synthesize.
        :param engine: The kind of engine used. Can be standard or neural.
        :param voice: The ID of the voice to use.
        :param audio_format: The audio format to return for synthesized speech. When
                             speech marks are synthesized, the output format is JSON.
        :param s3_bucket: The name of an existing Amazon S3 bucket that you have
                          write access to. Synthesis output is written to this bucket.
        :param lang_code: The language code of the voice to use. This has an effect
                          only when a bilingual voice is selected.
        :param include_visemes: When True, a second request is made to Amazon Polly
                                to synthesize a list of visemes, using the specified
                                text and voice. A viseme represents the visual position
                                of the face and mouth when saying part of a word.
        :param wait_callback: A callback function that is called periodically during
                              task processing, to give the caller an opportunity to
                              take action, such as to display status.
        :return: The audio stream that contains the synthesized speech and a list
                 of visemes that are associated with the speech audio.
        """
        try:
            kwargs = {
                "Engine": engine,
                "OutputFormat": audio_format,
                "OutputS3BucketName": s3_bucket,
                "Text": text,
                "VoiceId": voice,
            }
            if lang_code is not None:
                kwargs["LanguageCode"] = lang_code
            response = self.polly_client.start_speech_synthesis_task(**kwargs)
            speech_task = response["SynthesisTask"]
            logger.info("Started speech synthesis task %s.", speech_task["TaskId"])

            viseme_task = None
            if include_visemes:
                kwargs["OutputFormat"] = "json"
                kwargs["SpeechMarkTypes"] = ["viseme"]
                response = self.polly_client.start_speech_synthesis_task(**kwargs)
                viseme_task = response["SynthesisTask"]
                logger.info("Started viseme synthesis task %s.", viseme_task["TaskId"])
        except ClientError:
            logger.exception("Couldn't start synthesis task.")
            raise
        else:
            bucket = self.s3_resource.Bucket(s3_bucket)
            audio_stream = self._wait_for_task(
                10, speech_task["TaskId"], "speech", wait_callback, bucket
            )

            visemes = None
            if include_visemes:
                viseme_data = self._wait_for_task(
                    10, viseme_task["TaskId"], "viseme", wait_callback, bucket
                )
                visemes = [
                    json.loads(v) for v in viseme_data.read().decode().split() if v
                ]

            return audio_stream, visemes
```
+  For API details, see [StartSpeechSynthesisTask](https://docs.aws.amazon.com/goto/boto3/polly-2016-06-10/StartSpeechSynthesisTask) in *AWS SDK for Python (Boto3) API Reference*. 

### `SynthesizeSpeech`
<a name="polly_SynthesizeSpeech_python_3_topic"></a>

The following code example shows how to use `SynthesizeSpeech`.

**SDK for Python (Boto3)**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/polly#code-examples). 

```
class PollyWrapper:
    """Encapsulates Amazon Polly functions."""

    def __init__(self, polly_client, s3_resource):
        """
        :param polly_client: A Boto3 Amazon Polly client.
        :param s3_resource: A Boto3 Amazon Simple Storage Service (Amazon S3) resource.
        """
        self.polly_client = polly_client
        self.s3_resource = s3_resource
        self.voice_metadata = None


    def synthesize(
        self, text, engine, voice, audio_format, lang_code=None, include_visemes=False
    ):
        """
        Synthesizes speech or speech marks from text, using the specified voice.

        :param text: The text to synthesize.
        :param engine: The kind of engine used. Can be standard or neural.
        :param voice: The ID of the voice to use.
        :param audio_format: The audio format to return for synthesized speech. When
                             speech marks are synthesized, the output format is JSON.
        :param lang_code: The language code of the voice to use. This has an effect
                          only when a bilingual voice is selected.
        :param include_visemes: When True, a second request is made to Amazon Polly
                                to synthesize a list of visemes, using the specified
                                text and voice. A viseme represents the visual position
                                of the face and mouth when saying part of a word.
        :return: The audio stream that contains the synthesized speech and a list
                 of visemes that are associated with the speech audio.
        """
        try:
            kwargs = {
                "Engine": engine,
                "OutputFormat": audio_format,
                "Text": text,
                "VoiceId": voice,
            }
            if lang_code is not None:
                kwargs["LanguageCode"] = lang_code
            response = self.polly_client.synthesize_speech(**kwargs)
            audio_stream = response["AudioStream"]
            logger.info("Got audio stream spoken by %s.", voice)
            visemes = None
            if include_visemes:
                kwargs["OutputFormat"] = "json"
                kwargs["SpeechMarkTypes"] = ["viseme"]
                response = self.polly_client.synthesize_speech(**kwargs)
                visemes = [
                    json.loads(v)
                    for v in response["AudioStream"].read().decode().split()
                    if v
                ]
                logger.info("Got %s visemes.", len(visemes))
        except ClientError:
            logger.exception("Couldn't get audio stream.")
            raise
        else:
            return audio_stream, visemes
```
+  For API details, see [SynthesizeSpeech](https://docs.aws.amazon.com/goto/boto3/polly-2016-06-10/SynthesizeSpeech) in *AWS SDK for Python (Boto3) API Reference*. 

## Scenarios
<a name="scenarios"></a>

### Create a lip-sync application
<a name="polly_LipSync_python_3_topic"></a>

The following code example shows how to create a lip-sync application with Amazon Polly.

**SDK for Python (Boto3)**  
 Shows how to use Amazon Polly and Tkinter to create a lip-sync application that displays an animated face speaking along with the speech synthesized by Amazon Polly. Lip-sync is accomplished by requesting a list of visemes from Amazon Polly that match up with the synthesized speech.   
+ Get voice metadata from Amazon Polly and display it in a Tkinter application.
+ Get synthesized speech audio and matching viseme speech marks from Amazon Polly.
+ Play the audio with synchronized mouth movements in an animated face.
+ Submit asynchronous synthesis tasks for long texts and retrieve the output from an Amazon Simple Storage Service (Amazon S3) bucket.
 For complete source code and instructions on how to set up and run, see the full example on [GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/polly#code-examples).   

**Services used in this example**
+ Amazon Polly