TypeError: Invalid argument(s) 'pool_size' sent to create_engine() when using flask_sqlalchemy
<p>I'm using 
SQLAlchemy==1.0.9 and
Flask-SQLAlchemy==2.1
in my Flask application and want to connect to a sqlite db.</p>

<p>I get the error</p>

<pre><code>TypeError: Invalid argument(s) 'pool_size' sent to create_engine(), using configuration SQLiteDialect_pysqlite/NullPool/Engine.
</code></pre>

<p>because flask_sqlalchemy always tries to create the engine with the pool_size parameter.</p>

<p>As far as I understand the parameter pool_size is not allowed as an argument for the DefaultEngineStrategy in SQLAlchemy.</p>

<p>Does anyone know a workaround for this issue?</p>