<h1 id="heading-error">Error</h1>
<pre><code class="lang-python">[2023-04-30 17:46:44,787] ERROR in app: Exception on /api/message_groups [GET]
Traceback (most recent call last):
 ...
 File "/backend-flask/app.py", line 209, in data_message_groups
 model = MessageGroup.run(cognito_user_id=cognito_user_id)
 File "/backend-flask/services/message_group.py", line 22, in run
 dynamodb = ddb.client()
UnboundLocalError: local variable 'ddb' referenced before assignment
192.168.250.72 - - [30/Apr/2023 17:46:44] "GET /api/message_groups HTTP/1.1" 500 -
</code></pre>
<h1 id="heading-solution">Solution</h1>
<ul>
<li><code>UnboundLocalError</code> : <code>local variable 'ddb' referenced before assignment</code>
<ul>
<li>This error simply means that ddb has not assigned any value. Hence, an empty variable, or undefined.
</li>
<li>Find in which line the variable in question appears for the first time, and either give it a value, change the name or remove it.
</li>
</ul>
</li>
</ul>

# Error

```python
[2023-04-30 17:46:44,787] ERROR in app: Exception on /api/message_groups [GET]
Traceback (most recent call last):
    ...
  File "/backend-flask/app.py", line 209, in data_message_groups
    model = MessageGroup.run(cognito_user_id=cognito_user_id)
  File "/backend-flask/services/message_group.py", line 22, in run
    dynamodb = ddb.client()
UnboundLocalError: local variable 'ddb' referenced before assignment
192.168.250.72 - - [30/Apr/2023 17:46:44] "GET /api/message_groups HTTP/1.1" 500 -
```

# Solution

* `UnboundLocalError` : `local variable 'ddb' referenced before assignment`
    
    * This error simply means that ddb has not assigned any value. Hence, an empty variable, or undefined.
        
    * Find in which line the variable in question appears for the first time, and either give it a value, change the name or remove it.

Week 5 - UnboundLocalError: local variable 'ddb' referenced before assignment

Error

Solution