'Handle POST requests to get a first-party access token.'

def post(self, request, _backend):

    form = AccessTokenExchangeForm(request=request, oauth2_adapter=self.oauth2_adapter, data=request.POST)
    if (not form.is_valid()):
        return self.error_response(form.errors)
    user = form.cleaned_data['user']
    scope = form.cleaned_data['scope']
    client = form.cleaned_data['client']
    return self.exchange_access_token(request, user, scope, client)
