rename `key` to `access_token` in django-rest-auth?

My django-rest-auth on authentication sends the following response

{"key":"XXXXXXXXXXXXXX"}

Now i am using ember-simple-auth specifically oauth2-password-grant for authentication which expects access_token in response body. After looking at source code of ember js here, i found out that the value access_token is defined as string and cannot be changed. My question is how can i implement authentication using the two stack. Is there any way that i can rename key to access_token in django ?