I'm not quite making sense of where these Amadeus API Calls are coming from? - amadeus

Question

I have a code here which is in .js, but some of these variable aren't making sense. For example, the line stating var departure_from = segment.departure.iataCode; there isn't anything in the file that the .js would understand departure_from or segment.departure.iataCode. I'm assuming that the Amadeus website interprets this, but I can't seem to find anything on the Amadeus website that would tell me which of these JS code snippets to use in which circumstances.
jQuery(function($){
$( "#departureDate" ).datepicker( { dateFormat: "yy-mm-dd" } );
$( "#returnDate" ).datepicker( { dateFormat: "yy-mm-dd" } );
$( "#flight_offers_request_form" ).submit( function( event ) {
event.preventDefault();
$( "#response" ).html( '' );
$.ajax({
url: ajax_object.ajax_url,
type: "post",
dataType: 'JSON',
data: $( this ).serialize(),
})
.done ( function( response ) {
var responseObj = $.parseJSON( response );
var content = '';
content += '<p>Flight offers from ' +
$( '#originLocationCode' ).val() +
' to ' + $( '#destinationLocationCode' ).val() +
' departing on ' + $( '#departureDate' ).val() +
( ( $( '#returnDate' ).val() !== '' ) ? ( ' and returning on ' + $( '#returnDate' ).val() ) : '') +
' for ' + $( '#adults' ).val() +
' adult' + ( $( '#adults' ).val() > 1 ? 's.' : '.' ) +
'</p>';
content += '<table>';
content += '<tr><th>ID</th><th>Departure Place</th><th>Departure Time</th><th>Arrival Place</th><th>Arrival Time</th><th>Flight No</th><th>Duration</th><th>Total Price</th></tr>';
$.each( responseObj.data, function( idx, data ) {
var id = data.id;
var currency = data.price.currency;
var total = data.price.total;
var segment_count = 0;
$.each( data.itineraries, function( idx, itinerary ) {
$.each( itinerary.segments, function( idx, segment ) {
var departure_from = segment.departure.iataCode;
var departure_time = segment.departure.at;
var arrival_at = segment.arrival.iataCode;
var arrival_time = segment.arrival.at;
var carrierCode = segment.carrierCode;
var number = segment.number;
var duration = segment.duration;
content += '<tr>';
content += '<td>' + ( ( segment_count === 0 ) ? id : '' ) + '</td><td>';
content += departure_from + '</td><td>' +
departure_time + '</td><td>' +
arrival_at + '</td><td>' +
arrival_time + '</td><td>' +
carrierCode + ' ' + number +
'</td><td>' +
duration + '</td>';
content += '<td>' + ( ( segment_count === 0 ) ? currency + ' ' + total : '' ) + '</td><td>';
content += '</tr>';
segment_count++;
})
})
})
content += '</table>';
$( '#response' ).html( content );
})
.fail(function( jqXHR, textStatus ) {
$( "#response" ).html( '<p>' + jqXHR.responseText + '</p>' );
})
})
});