Strava uses OAuth v2 for Authentication.
Register a new application at the Strava API, and
fill Client ID and Client Secret from strava.com values in the settings:
SOCIAL_AUTH_STRAVA_KEY = ''
SOCIAL_AUTH_STRAVA_SECRET = ''
extra scopes can be defined by using:
SOCIAL_AUTH_INSTAGRAM_AUTH_EXTRA_ARGUMENTS = {'scope': 'likes comments relationships'}