running the app as-is shows the following error, please support.

$ flutter run
Using hardware rendering with device sdk gphone x86. If you get graphics artifacts, consider enabling software rendering with "--enable-software-rendering".
Launching lib/main.dart on sdk gphone x86 in debug mode...
                                                                        
Compiler message:                                                       
lib/item_screen.dart:1484:26: Error: 'RangeSlider' is imported from both 'package:flutter/src/material/range_slider.dart' and 'package:flutter_range_slider/src/flutter_range_slider.dart'.
              child: new RangeSlider(                                   
                         ^^^^^^^^^^^                                    
Target kernel_snapshot failed: Exception: Errors during snapshot creation: null
build failed.                                                           
                                                                        
FAILURE: Build failed with an exception.                                
                                                                        
* Where:                                                                
Script '/...../flutter/packages/flutter_tools/gradle/flutter.gradle' line: 780
                                                                        
* What went wrong:                                                      
Execution failed for task ':app:compileFlutterBuildDebug'.              
> Process 'command '/...../flutter/bin/flutter'' finished with non-zero exit value 1
                                                                        
* Try:                                                                  
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
                                                                        
* Get more help at https://help.gradle.org                              
                                                                        
BUILD FAILED in 7s                                                      
Running Gradle task 'assembleDebug'...                                  
Running Gradle task 'assembleDebug'... Done                         7.7s
Gradle task assembleDebug failed with exit code 1

Hello, Myself Siyona Lodha! I wanted to contribute to your project for my college open source lab. Can you please assign me some tasks and give me an opportunity to become a contributor?

Thank you.