def parse_sequence(lines, constructor="".join):
    """Parses a GenBank sequence block. Doesn't care about ORIGIN line."""
    result = []
    exclude = b"0123456789 \t\n\r/"
    strip_table = dict([(c, None) for c in exclude])

    for i in lines:
        if i.startswith("ORIGIN"):
            continue

        result.append(i.translate(strip_table))
    return constructor(result)