niwibe/djorm-ext-pool — pull request #1 by jeethu (2012-12-17 14:52:20+00:00)
Title: Issue with MySQL

While trying to use this with MySQL, I was getting a strange traceback from sqlalchemy.

```
Traceback (most recent call last):
File "/Users/jeethu/Envs/bb/lib/python2.7/site-packages/django/core/management/commands/runserver.py", line 88, in inner_run
self.validate(display_num_errors=True)
File "/Users/jeethu/Envs/bb/lib/python2.7/site-packages/django/core/management/base.py", line 249, in validate
num_errors = get_validation_errors(s, app)
File "/Users/jeethu/Envs/bb/lib/python2.7/site-packages/django/core/management/validation.py", line 102, in get_validation_errors
connection.validation.validate_field(e, opts, f)
File "/Users/jeethu/Envs/bb/lib/python2.7/site-packages/django/db/backends/mysql/validation.py", line 14, in validate_field
db_version = self.connection.get_server_version()
File "/Users/jeethu/Envs/bb/lib/python2.7/site-packages/django/db/backends/mysql/base.py", line 338, in get_server_version
self.cursor()
File "/Users/jeethu/Envs/bb/lib/python2.7/site-packages/django/db/backends/__init__.py", line 250, in cursor
cursor = self.make_debug_cursor(self._cursor())
File "/Users/jeethu/Envs/bb/lib/python2.7/site-packages/django/db/backends/mysql/base.py", line 322, in _cursor
self.connection = Database.connect(**kwargs)
File "/Users/jeethu/Envs/bb/lib/python2.7/site-packages/sqlalchemy/pool.py", line 1010, in connect
return self.get_pool(*args, **kw).connect()
File "/Users/jeethu/Envs/bb/lib/python2.7/site-packages/sqlalchemy/pool.py", line 981, in get_pool
return self.pools[key]
TypeError: unhashable type: 'dict'
```

This is because `MySQLdb.connections.Connection` takes an optional `conv` parameter which is a dictionary of [converters](http://mysql-python.sourceforge.net/MySQLdb-1.2.2/public/MySQLdb.converters-module.html).
This makes the connection parameters unhashable, and thus the error.
Here's a very hacky fix for this issue.