You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: paypal.rs
    path of file: ./repos/hyperswitch/crates/router/src/types/api/connector_onboarding
    
    the code of the file until where you have to start completion: use api_models::connector_onboarding as api;
use error_stack::{IntoReport, ResultExt};

use crate::core::errors::{
    
    pub fn extract_merchant_details_url(self, paypal_base_url: &str) -> RouterResult<String> {
        self.links
            .first()
            .and_then(|link| link.href.strip_prefix('/'))
            .map(|link| format!("{}{}", paypal_base_url, link))
            .ok_or(ApiErrorResponse::InternalServerError)
            .into_report()
            .attach_printable("Merchant details not received in onboarding status")
    }