for unstranded data with novel transcripts single exon genes
    will have no strand information. single exon novel genes are also
    a source of noise in the Cufflinks assembly so this removes them

def strand_unknown(db, transcript):
    """
    for unstranded data with novel transcripts single exon genes
    will have no strand information. single exon novel genes are also
    a source of noise in the Cufflinks assembly so this removes them
    """
    features = list(db.children(transcript))
    strand = features[0].strand
    if strand == ".":
        return True
    else:
        return False