# Receive an SMS Message with Python SDK

 Note:
Before you can get started, you need the following already set up:

- 
- [Python](https://www.python.org/) and a familiarity with how to create a new app.
- [PIP (package installer for Python)](https://pypi.org/project/pip/) and a familiarity with how to install Python modules.
- [Flask](https://flask.palletsprojects.com/en/2.3.x/installation/) and a familiarity with how to set up a Flask environment and app.
- [ngrok](https://ngrok.com/). You'll use ngrok to open a tunnel to your local server.


Learn how to handle incoming SMS messages in a Python application with the Sinch Python SDK.

Steps:
1. [Install](#install-the-sdk) the Python SDK
2. [Set up](#set-up-your-environment) your environment
3. [Set up](#set-up-your-python-application) your Python application
4. [Configure](#configure-your-callback-url) your callback URL
5. [Test](#test-the-application) your application


## Install the SDK

The easiest way to install the SDK is using [`pip`](https://pypi.org/project/pip/):

1. Open a command prompt or terminal to the local repository folder.
2. Execute the following command:

```shell
pip install sinch
```


## Set up your environment

Now you can start setting up your environment.

Create a new folder where you want your app project and open a command prompt to that location. Create a new environment with the following command:


```shell
py -3 -m venv venv
```

Activate the environment using the following command:


```shell
venv/Scripts/activate
```

### Install your dependencies

We will be using Flask to create a lightweight webserver that will listen for requests from the Sinch servers to handle incoming calls. Additionally, we'll be using the `requests` module to make HTTP requests.

Use the following commands to install the `Flask` and `requests` modules:


```shell
pip install Flask
pip install requests
```

## Set up your Python application

Create a new file named `app.py` and paste the provided "handle-incoming.py" code into the file.

handle-incoming.py
import os
import sinch
from flask import Flask, request


app = Flask(__name__)

sinch_client = sinch.SinchClient(
    key_id="YOUR_KEY_ID",
    key_secret="YOUR_KEY_SECRET",
    project_id="YOUR_PROJECT_ID"
)


@app.route('/', methods=['POST'])
def result():
    inbound_message = request.get_json()
    print(inbound_message)

    if all(key in inbound_message for key in ["body", "to", "from"]):
        sinch_client.sms.batches.send(
            body="Thank you for using the Sinch SDK. You sent: " + inbound_message["body"],
            delivery_report="none",
            to=[inbound_message["from"]],
            from_=inbound_message["to"]
        )

        return "Inbound message received", 200

    else:
        return "Invalid data", 400

### Modify your application

The code provided includes placeholder parameters. You'll need to update the parameters detailed in the following subsections with your values.

#### Initialize the client

Before initializing a client using this SDK, you'll need three pieces of information:

- Your Project ID
- An access key ID
- An access key Secret


These values can be found on the [<b>Access Keys</b>](https://dashboard.sinch.com/settings/access-keys) page of the Sinch Build Dashboard. You can also [create new access key IDs and Secrets](https://community.sinch.com/t5/Conversation-API/How-to-get-your-access-key-for-Conversation-API/ta-p/8120), if required.

Note
If you have trouble accessing the above link, ensure that you have gained access to the [Conversation API](https://dashboard.sinch.com/convapi/overview) by accepting the corresponding terms and conditions.

Ensure that you save the file.

### Start your web server and set up a tunnel

1. Start the server by executing the following command:

```shell
flask run
```
By default, your web server is started on port 5000.
2. Now you need to open a tunnel to the server you just set up. We are using [ngrok](https://ngrok.com/) for this. If you don't have ngrok installed already you can install it with the following command:

```shell
npm install ngrok -g
```
3. In the terminal or command prompt, enter:

```shell
ngrok http 5000
```
You will see a screen like the following.
![ngrok screenshot](/assets/ngrok.135751fc8aa7c936230a2a88bff2263644a1d1737263acc00294006a34b0f60b.c6cba068.png)
4. On the highlighed "Forwarding" line, copy the address ending in `.ngrok.io`.


## Configure your Callback URL

Next, configure a Callback URL for your Sinch account.

1. On your [Sinch Build Dashboard](https://dashboard.sinch.com/sms/api/rest)-> Service APIs click on the service plan ID link.
2. In “Callback URL” click **Add Callback URL** and paste in the HTTPS address referred to in the previous section.


## Test the application

Now that your server is running and your webhook is configured, you can test the application.

From your messaging platform, send your SMS app a message. You will receive a message back in response on your mobile handset.

## Additional resources

- Visit our [API specification](/docs/sms/api-reference/) to test more endpoints.