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        private void InitializeAmazonClients()
        {
            _credentialsValid = TryGetAwsCredentials(out _awsCredentials);
            if (!_credentialsValid)
                throw new Exception("Not able to find aws credentials.");
            if (_transcribeClient == null)
                _transcribeClient = new AmazonTranscribeServiceClient(_awsCredentials, Amazon.RegionEndpoint.EUWest2);
            if (_s3Client == null)
                _s3Client = new AmazonS3Client(_awsCredentials, Amazon.RegionEndpoint.EUWest2);
            if (_translateClient == null)
                _translateClient = new AmazonTranslateClient(_awsCredentials, Amazon.RegionEndpoint.EUWest1);
            if (_pollyClient == null)
                _pollyClient = new AmazonPollyClient(_awsCredentials, Amazon.RegionEndpoint.EUWest1);
        }

        private bool TryGetAwsCredentials(out AWSCredentials awsCredentials)
        {
            CreateSettingsStoreFolderIfNotExists();
            var chain = new CredentialProfileStoreChain();
            if (!chain.TryGetAWSCredentials(_settings.CredentialProfile, out awsCredentials))
            {
                CreateAwsCredentials();
                if (!chain.TryGetAWSCredentials(_settings.CredentialProfile, out awsCredentials))
                {
                    return false;
                }
            }
            return true;
        }

        private void CreateAwsCredentials()
        {
            var options = new CredentialProfileOptions
            {
                AccessKey = _settings.AccessKey,
                SecretKey = _settings.SecretKey
            };
            var profile = new CredentialProfile(_settings.CredentialProfile, options);
            profile.Region = RegionEndpoint.USWest1;
            var sharedFile = new SharedCredentialsFile();
            sharedFile.RegisterProfile(profile);
        }

        private static void CreateSettingsStoreFolderIfNotExists()
        {
            string settingsStoreFolder = "";
            #if BCL
            settingsStoreFolder = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "AWSToolkit");
            #else
            settingsStoreFolder = Environment.GetEnvironmentVariable("HOME");
            if (string.IsNullOrEmpty(settingsStoreFolder))
            settingsStoreFolder = Environment.GetEnvironmentVariable("USERPROFILE");
            settingsStoreFolder = Path.Combine(settingsStoreFolder, "AppData", "Local", "AWSToolkit");
            #endif
            if (!Directory.Exists(settingsStoreFolder))
                Directory.CreateDirectory(settingsStoreFolder);
        }

        public bool DownloadFileFromS3(string filePath, string bucketName, string objectName)
        {
            try
            {
                var fileTransferUtility = new TransferUtility(_s3Client);
                fileTransferUtility.DownloadAsync(filePath, bucketName, objectName).Wait();
                return true;
            }
            catch (AmazonS3Exception e)
            {
                _logger.LogError($"Error encountered on server. Message:'{0}' when writing an object", e.Message);
            }
            catch (Exception e)
            {
                _logger.LogError($"Unknown encountered on server. Message:'{0}' when writing an object", e.Message);
            }
            return false;
        }

       
        public string UploadFileToS3(string filePath, string bucketName, string objectName = null)
        {
            try
            {
                var fileTransferUtility = new TransferUtility(_s3Client);
                string s3ObjectName = objectName ?? Path.GetFileName(filePath);
                var fileTransferUtilityRequest = new TransferUtilityUploadRequest
                {
                    BucketName = bucketName,
                    FilePath = filePath,
                    StorageClass = S3StorageClass.StandardInfrequentAccess,
                    PartSize = 6291456, // 6 MB.
                    Key = s3ObjectName,
                    CannedACL = S3CannedACL.PublicRead
                };
                fileTransferUtility.UploadAsync(fileTransferUtilityRequest).Wait();
                return s3ObjectName;
            }
            catch (AmazonS3Exception e)
            {
                _logger.LogError($"Error encountered on server. Message:'{0}' when writing an object", e.Message);
            }
            catch (Exception e)
            {
                _logger.LogError($"Unknown encountered on server. Message:'{0}' when writing an object", e.Message);
            }
            return null;
        }