Adding a variable as filename for a file downloaded from s3

Question

I created a CloudFormation templates that downloads several files from S3 basing on the parameters the user chooses.

For 1 of those downloads the file can change depending on the value of a variable and I can add that variable on the s3 link to be downloaded, but I can't find the right syntax to change the name of the file created(${Filename}):

'c:\cfn\modules\'${Filename}:
          Condition: IsCF
          source: !Sub 
            - >-
              https://${SoftwareS3BucketName}.${SoftwareS3Region}.${SoftwareS3BucketRegion}.amazonaws.com/ProductsPackages/CF5/${Filename}
            - SoftwareS3Region: !If 
                - GovCloudCondition
                - s3-us-gov-west-1
                - s3
          authentication: S3AccessCredsSoftware