How to use custom function for account activation in django graphql auth

Question

I am using django-graphql-auth to send account activation email.

It has below method,

https://github.com/PedroBern/django-graphql-auth/blob/master/graphql_auth/mixins.py#L200

However I need to use my own custom function since I am using third party api service.

Using my function I am able to send the email however I am not sure how can I override the default behavior.

I am seeing there is an async_email_fucn at below, https://github.com/PedroBern/django-graphql-auth/blob/master/graphql_auth/mixins.py#L219

Please suggest.