def _format_mongodb_uri(parsed_uri):
    """
    Painstakingly reconstruct a MongoDB URI parsed using pymongo.uri_parser.parse_uri.

    :param parsed_uri: Result of pymongo.uri_parser.parse_uri
    :type parsed_uri: dict

    :return: New URI
    :rtype: str | unicode
    """
    user_pass = ''
    if parsed_uri.get('username') and parsed_uri.get('password'):
        user_pass = '{username!s}:{password!s}@'.format(**parsed_uri)

    _nodes = []
    for host, port in parsed_uri.get('nodelist'):
        if ':' in host and not host.endswith(']'):
            # IPv6 address without brackets
            host = '[{!s}]'.format(host)
        if port == 27017:
            _nodes.append(host)
        else:
            _nodes.append('{!s}:{!s}'.format(host, port))
    nodelist = ','.join(_nodes)

    options = ''
    if parsed_uri.get('options'):
        _opt_list = []
        for key, value in parsed_uri.get('options').items():
            if isinstance(value, bool):
                value = str(value).lower()
            _opt_list.append('{!s}={!s}'.format(key, value))
        options = '?' + '&'.join(_opt_list)

    db_name = parsed_uri.get('database') or ''

    res = "mongodb://{user_pass!s}{nodelist!s}/{db_name!s}{options!s}".format(
        user_pass=user_pass,
        nodelist=nodelist,
        db_name=db_name,
        # collection is ignored
        options=options)
    return res
Painstakingly reconstruct a MongoDB URI parsed using pymongo.uri_parser.parse_uri.

    :param parsed_uri: Result of pymongo.uri_parser.parse_uri
    :type parsed_uri: dict

    :return: New URI
    :rtype: str | unicode