update readme with sample for auth

Author: emnbdx

README.md

@@ -1,12 +1,6 @@
-# openapi-client
-HelloAsso auto-generated SDK
+# helloasso-python
 
-This Python package is automatically generated by the [OpenAPI Generator](https://openapi-generator.tech) project:
-
-- API version: public
-- Package version: 1.0.0
-- Generator version: 7.10.0
-- Build package: org.openapitools.codegen.languages.PythonClientCodegen
+The HelloAsso Python library offers a straightforward way to interact with the HelloAsso API in Python applications. It features a collection of pre-built classes for API resources that automatically adapt to API responses, ensuring flexibility across different versions of the HelloAsso API.
 
 ## Requirements.
 
@@ -18,9 +12,9 @@ Python 3.8+
 If the python package is hosted on a repository, you can install directly using:
 
 ```sh
-pip install git+https://github.com/GIT_USER_ID/GIT_REPO_ID.git
+pip install helloasso-python
 ```
-(you may need to run `pip` with root permission: `sudo pip install git+https://github.com/GIT_USER_ID/GIT_REPO_ID.git`)
+(you may need to run `pip` with root permission: `sudo pip install helloasso-python`)
 
 Then import the package:
 ```python
@@ -235,23 +229,116 @@ Class | Method | HTTP request | Description
  - [ResultsWithPaginationModelSynchronizableFormModel](docs/ResultsWithPaginationModelSynchronizableFormModel.md)
  - [ResultsWithPaginationModelSynchronizableOrganizationModel](docs/ResultsWithPaginationModelSynchronizableOrganizationModel.md)
 
+## Authorization
 
-<a id="documentation-for-authorization"></a>
-## Documentation For Authorization
-
+We use OAuth2 for authentication, so to avoid reinventing the wheel, we recommend using the [Authlib](https://pypi.org/project/Authlib) package
 
-Authentication schemes defined for the API:
-<a id="OAuth2"></a>
-### OAuth2
+### Prerequisite
+Install the Authlib package:
 
-- **Type**: OAuth
-- **Flow**: application
-- **Authorization URL**: 
-- **Scopes**: N/A
+```bash
+pip install requests
+pip install Authlib
+```
 
+### Client Credentials Flow
+```python
+from authlib.integrations.requests_client import OAuth2Session
+
+# Configuration
+client_id = 'your_client_id'
+client_secret = 'your_client_secret'
+token_url = 'https://api.helloasso.com/oauth2/token'
+
+# Create an OAuth2 session
+client = OAuth2Session(client_id, client_secret)
+
+# Get an access token
+def get_access_token():
+    token = client.fetch_token(token_url, grant_type='client_credentials')
+    print("Access Token:", token['access_token'])
+    print("Expires In:", token['expires_in'])
+    print("Refresh Token:", token['refresh_token'])
+    return token
+
+# Usage
+get_access_token()
+```
 
-## Author
+### Refresh Token Flow
+```python
+from authlib.integrations.requests_client import OAuth2Session
+
+# Configuration
+client_id = 'your_client_id'
+client_secret = 'your_client_secret'
+token_url = 'https://api.helloasso.com/oauth2/token'
+
+# Refresh the token
+def refresh_access_token(refresh_token):
+    client = OAuth2Session(client_id, client_secret)
+    token = client.refresh_token(token_url, refresh_token=refresh_token)
+    print("New Access Token:", token['access_token'])
+    print("Expires In:", token['expires_in'])
+    print("New Refresh Token:", token['refresh_token'])
+    return token
+
+# Usage
+refresh_access_token('your_refresh_token')
+```
 
+### Authorization Code Flow
+```python
+import base64
+import hashlib
+import os
+from authlib.integrations.requests_client import OAuth2Session
+
+# Configuration
+client_id = 'your_client_id'
+client_secret = 'your_client_secret'
+authorize_url = 'https://auth.helloasso.com/authorize'
+token_url = 'https://api.helloasso.com/oauth2/token'
+redirect_uri = 'https://your-app.com/callback'
+
+# PKCE Helper Functions
+def generate_code_verifier():
+    """Generate a high-entropy code_verifier."""
+    return base64.urlsafe_b64encode(os.urandom(32)).rstrip(b'=').decode('utf-8')
+
+def generate_code_challenge(code_verifier):
+    """Generate a code_challenge based on the code_verifier."""
+    code_challenge = hashlib.sha256(code_verifier.encode('utf-8')).digest()
+    return base64.urlsafe_b64encode(code_challenge).rstrip(b'=').decode('utf-8')
+
+# Step 1: Generate the Authorization URL
+def get_authorization_url():
+    # Generate PKCE parameters
+    code_verifier = generate_code_verifier()
+    code_challenge = generate_code_challenge(code_verifier)
+
+    client = OAuth2Session(client_id, client_secret, redirect_uri=redirect_uri)
+    authorization_url, state = client.create_authorization_url(authorize_url, code_challenge=code_challenge, code_challenge_method='S256')
+    print("Authorization URL: ", authorization_url)
+    print("Code verifier: ", code_verifier)
+
+# Step 2: Exchange the authorization code for an access token
+def get_access_token_from_code(authorization_response, code_verifier):
+    client = OAuth2Session(client_id, client_secret, redirect_uri=redirect_uri)
+    token = client.fetch_token(token_url, authorization_response=authorization_response, code_verifier=code_verifier)
+    print("Access Token: ", token['access_token'])
+    print("Expires In: ", token['expires_in'])
+    print("Refresh Token: ", token['refresh_token'])
+
+# Usage
+get_authorization_url()
+# After user authorizes, exchange the code (passed in the redirect URL callback)
+#get_access_token_from_code('your_authorization_code', 'your_code_verifier')
+```
 
+## About this package
 
+This SDK is automatically generated by the [OpenAPI Generator](https://openapi-generator.tech) project:
 
+- Generator version: 7.10.0
+- Build package: org.openapitools.codegen.languages.PythonClientCodegen