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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def download_file(bucket_name, path, target, sagemaker_session):
 """Download a Single File from S3 into a local path Args: bucket_name (str):
 S3 bucket name path (str):
 file path within the bucket target (str):
 destination directory for the downloaded file. sagemaker_session (:class:`sagemaker.session.Session`):
 a sagemaker session to interact with S3. """

    path = path.lstrip('/')
    boto_session = sagemaker_session.boto_session

    s3 = boto_session.resource('s3')
    bucket = s3.Bucket(bucket_name)
    bucket.download_file(path, target)