def get(self, id, pk='id', deleted=False):
        try:
            if pk == 'id':
                id = int(id)
            if deleted:
                spec = {pk: id}
            else:
                spec = {pk: id, 'data': {'$exists': 1}}
            fields = {'_id': 0}
            row = self.db.docs.find_one(spec, fields)
        except Exception as e:
            raise DatabaseException(e)
        if row:
            return Document(**row)
        raise NotFoundError('%s %s not found' % (pk, id))
def _convertretoglobs(repat):
    """Attempt to convert a regular expression pattern to glob patterns.

    A single regular expression pattern might be converted into multiple
    glob patterns.

    Return None if conversion is unsupported.

    >>> _convertretoglobs("abc*") is None
    True
    >>> _convertretoglobs("xx/yy/(?!zz/kk)")
    ['xx/yy/**', '!xx/yy/zz/kk/**']
    >>> _convertretoglobs("x/y/(?:.*/)?BUCK")
    ['x/y/**/BUCK']
    """
    m = _repat1.match(repat)
    if m:
        prefix, excluded = m.groups()
        return ["%s/**" % prefix, "!%s/%s/**" % (prefix, excluded)]
    m = _repat2.match(repat)
    if m:
        prefix, name = m.groups()
        return ["%s/**/%s" % (prefix, name)]
    return None