Pre-Request in swagger

I am configuring Swagger in my project using Python Flask. The API which I am invoking from swagger needs the token bearer and that token bearer can be fetched by invoking other API(/GetToken) ( which need basic auth).

I need to automate this process when ever user is invoking a API from swagger the swagger should automatically call /GetToken and set the bearer token. (kind of Pre-request script in postman)

I tried searching for any solution in swagger documentation by found None.