Changing the default database

[SindhuBairavi]

According to this, so when I instantiate iepy, sqlite db is created. I tried modifying this to MySQL after creating an instance, but I get the below errors while migrating, which doesn't let me proceed.

SystemCheckError: System check identified some issues:
ERRORS:
corpus.EntityKind.name: (mysql.E001) MySQL does not allow unique CharFields to have a max_length > 255.
corpus.GazetteItem.text: (mysql.E001) MySQL does not allow unique CharFields to have a max_length > 255.

Any options that can help me fix this?