def showDifferences(seq1, seq2):
    """Returns a string highligthing differences between seq1 and seq2:
	
	* Matches by '-'
	
	* Differences : 'A|T'
	
	* Exceeded length : '#'
	
	"""
    ret = []
    for i in range(max(len(seq1), len(seq2))):
        if i >= len(seq1):
            c1 = '#'
        else:
            c1 = seq1[i]
        if i >= len(seq2):
            c2 = '#'
        else:
            c2 = seq2[i]
        if c1 != c2:
            ret.append('%s|%s' % (c1, c2))
        else:
            ret.append('-')
    return ''.join(ret)
