CopyObject copies the `inputKey` in the inputBucket to `outputKey` in the outputBucket.

DeleteObject delete the key in the specified bucket.

DeleteObjects delete the keys in the specified bucket.

DownloadObject downloads a file from an S3 bucket given the bucket and key.

ListBucket returns a slice of the files at an S3 bucket at a given prefix.

ListFolders returns the folders stored at `prefix` in the bucket `bucket`.

ListNObjectsInBucket returns a slice of the files at an S3 bucket at a given prefix.

ObjectExists returns a boolean of whether the key exists in the bucket.

RenameObject renames the `inputKey` in the bucket to `outputKey`.

UploadObject uploads a slice of bytes to a specific path and S3 bucket.

CannotReadError is used in the tests.