old_contents: /**
   * Returns sorting query for past/upcoming launches
  */
  
  const lowerCase = require("lower-case")
  
  exports.launchSort = (req) => {
    const query = {}
  
    if (lowerCase(req.query.order) === "asc") {
      query.flight_number = 1
    } else if (lowerCase(req.query.order) === "desc") {
      query.flight_number = -1
    } else {
      query.flight_number = 1
    }
  
    return query
  }
  
new_contents: /**
   * Returns sorting query for past/upcoming launches
  */
  
  const lowerCase = require('lower-case');
  
  exports.launchSort = (req) => {
    const query = {};
  
    if (lowerCase(req.query.order) === 'asc') {
      query.flight_number = 1;
    } else if (lowerCase(req.query.order) === 'desc') {
      query.flight_number = -1;
    } else {
      query.flight_number = 1;
    }
  
    return query;
  };
  
subject: format launch sort with airbnb style