Updated the readme

README.md

@@ -6,6 +6,12 @@ Lolafect is a collection of Python bits that help us build our Prefect flows.
 
 You can find below examples of how to leverage `lolafect` in your flows.
 
+**_Note: the code excerpts below are simplified for brevity and won't run 
+as-is. If you want to see perfect examples, you might want to check the tests
+in this repository._**
+
+### Config
+
 **Let the `LolaConfig` object do the boilerplate env stuff for you**
 
 ```python
@@ -36,6 +42,8 @@ lolaconfig = build_lolaconfig(
 )
 ```
 
+### Connections
+
 **Connect to a Trino server**
 
 ```python
@@ -52,6 +60,66 @@ with Flow(...) as flow:
     )
 ```
 
+**Open an SSH tunnel**
+
+```python
+from lolafect.connections import open_ssh_tunnel_with_s3_pkey, close_ssh_tunnel
+
+with Flow(...) as flow:
+    # You probably want to fetch these args from lolaconfig.SSH_CREDENTIALS and lolaconfig.DW_CREDENTIALS
+    tunnel = open_ssh_tunnel_with_s3_pkey( 
+        s3_bucket_name="some-bucket",
+        ssh_tunnel_credentials={...},
+        remote_target_host="some-host-probably-mysql",
+        remote_target_port=12345,
+    )
+    # Tunnel is now alive. tunnel.is_active == True
+    close_ssh_tunnel(tunnel=tunnel)  
+```
+
+**Connect to a MySQL instance**
+```python
+from lolafect.connections import connect_to_mysql, close_mysql_connection
+
+with Flow(...) as flow:
+    connection = connect_to_mysql.run(
+        mysql_credentials={...}, # You probably want to get this from TEST_LOLACONFIG.DW_CREDENTIALS
+    )
+    connection.cursor().execute("SELECT 1")
+    close_mysql_connection.run(connection=connection)
+
+# Want to connect through an SSH tunnel? Open the tunnel normally and then
+# override the host and port when connecting to MySQL.
+
+from lolafect.connections import (
+    open_ssh_tunnel_with_s3_pkey, 
+    get_local_bind_address_from_ssh_tunnel,
+    close_ssh_tunnel
+)
+    
+with Flow(...) as flow:
+    # You probably want to fetch these args from lolaconfig.SSH_CREDENTIALS and lolaconfig.DW_CREDENTIALS
+    tunnel = open_ssh_tunnel_with_s3_pkey( 
+        s3_bucket_name="some-bucket",
+        ssh_tunnel_credentials={...},
+        remote_target_host="the-mysql-host",
+        remote_target_port=3306,
+    )
+
+    connection = connect_to_mysql.run(
+        mysql_credentials={...}, # You probably want to get this from TEST_LOLACONFIG.DW_CREDENTIALS
+        overriding_host_and_port=get_local_bind_address_from_ssh_tunnel.run(
+            tunnel=tunnel # This will open the connection through the SSH tunnel instead of straight to MySQL
+        ),
+    )
+
+    connection.cursor().execute("SELECT 1")
+
+    close_mysql_connection.run(connection=connection)
+    close_ssh_tunnel.run(tunnel=tunnel)
+```
+
+### Slack
 
 **Send a warning message to slack if your tasks fails**