import boto3

def upload_file( filename ):
    session = boto3.Session()
    s3_client = session.client( 's3' )

    try:
        print "Uploading file:", filename

        tc = boto3.s3.transfer.TransferConfig()
        t = boto3.s3.transfer.S3Transfer( client=s3_client,
                                         config=tc )

        t.upload_file( filename, 'my-bucket-name', 'name-in-s3.dat' )

    except Exception as e:
        print "Error uploading: %s" % ( e )