The function is empty or cannot be parsed. Make sure not to modify code outside of the designated area.

import 'dart:convert'; 
import 'dart:math' as math; 
import 'package:http/http.dart' as http; 
import 'package:flutter/material.dart'; 
import 'package:google_fonts/google_fonts.dart'; 
import 'package:intl/intl.dart'; 
import 'package:timeago/timeago.dart' as timeago; 
import '/flutter_flow/lat_lng.dart'; 
import '/flutter_flow/place.dart'; 
import '/flutter_flow/uploaded_file.dart'; 
import '/flutter_flow/custom_functions.dart'; 
import '/backend/supabase/supabase.dart'; 
import '/auth/supabase_auth/auth_util.dart'; 

Future<String> insertDemandDetails( 
String? quantity, String? observation, 
) { /// MODIFY CODE ONLY BELOW THIS LINE // I need custom function for inserting data in table demandDetails 
try { 
final url = 'https://xgwxjlnamnvzgdjxdoeh.supabase.co/rest/v1/demandDetails'; // Ensure this is the correct endpoint for your table 
final data = { 'quantity': quantity, 'observation': observation, }; // Perform HTTP POST request to insert data into demandDetails table
 // Making the HTTP POST request and returning the Future 
return http.post( Uri.parse(url), 
headers: { 
'Content-Type': 'application/json', 
'apikey': 'YOUR_SUPABASE_ANON_KEY', 
// Replace with your actual Supabase Anon Key 
'Authorization': 'Bearer YOUR_SUPABASE_ANON_KEY', // Replace with your actual Supabase Anon Key 
}, 
body: json.encode(data), ).then((response) { // Handling the response 
if (response.statusCode == 201) { 
final responseBody = json.decode(response.body); 
return 'Data inserted successfully: ${responseBody['id']}'; // Assuming id is returned upon successful insertion 
} else { 
print('Failed to insert data into demandDetails table: 
${response.statusCode} - ${response.body}'); 
return 'Failed to insert data into demandDetails table'; 
} })
.catchError((error) { 
print('Error inserting data into demandDetails table: $error'); 
return 'Error inserting data into demandDetails table'; }); 
} 
catch (error) { 
print('Error inserting data into demandDetails table: $error'); 
return Future.value('Error inserting data into demandDetails table'); 
} 
/// MODIFY CODE ONLY ABOVE THIS LINE 
}