def get_object_size(boto_s3_object):
    """Return the size of the S3 object in MB

    Parameters
    ----------
    boto_s3_object : boto object

    Returns
    -------
    object_size : float (in MB)
    """
    boto_s3_object.load()
    return boto_s3_object.meta.data['ContentLength'] / 2.0 ** 20
