How to use the pymysql.converters.conversions.copy function in PyMySQL

def getConnection(self, nodb=False):
        """
        @rtype L{pymysqlConnection}
        """
        if not self.startMysqld():
            raise RuntimeError("Can't start mysqld server!")

        if nodb:
            conn = pymysql.connect(unix_socket=self.getSocket(), user=self.getUser(), passwd=self.getPassword())
        else:

            if self._conn:
                return self._conn

            conv = pymysql.converters.conversions.copy()
            conv[246]=float     # convert decimals to floats
            conv[10]=str        # convert dates to strings

            conn = self._conn = pymysql.connect(
                unix_socket=self.getSocket(),
                user=self.getUser(),
                passwd=self.getPassword(),
                db=self.getDbName(),
                conv=conv
            )
            self._conn.autocommit(self.getAutocommit())

        cur = conn.cursor()
        if not self.getAutocommit():
            cur.execute("SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED")
        cur.close()

:return converter: Converter object
    """

    converter = None
    try:
        import MySQLdb.converters  # pylint: disable=import-error
        from MySQLdb.constants import FIELD_TYPE  # pylint: disable=import-error
        converter = MySQLdb.converters.conversions.copy()
        converter[FIELD_TYPE.DECIMAL] = float
        converter[FIELD_TYPE.NEWDECIMAL] = float
    except ImportError:
        try:
            from pymysql.constants import FIELD_TYPE
            from pymysql.converters import conversions as conv
            converter = conv.copy()
            converter[FIELD_TYPE.DECIMAL] = float
            converter[FIELD_TYPE.NEWDECIMAL] = float
        except ImportError:
            raise RucioException('Trying to use MySQL without mysql-python or pymysql installed!')
    return converter

def connect(self, database=None, user=None, password=None, host=None, port=None, charset=None):
        db = (database or self.dbname)
        user = (user or self.user)
        password = (password or self.password)
        host = (host or self.host)
        port = (port or self.port)
        charset = (charset or self.charset)
        conv = conversions.copy()
        conv.update({
            FIELD_TYPE.TIMESTAMP: lambda obj: (convert_mysql_timestamp(obj) or obj),
            FIELD_TYPE.DATETIME: lambda obj: (convert_datetime(obj) or obj),
            FIELD_TYPE.TIME: lambda obj: (convert_timedelta(obj) or obj),
            FIELD_TYPE.DATE: lambda obj: (convert_date(obj) or obj),
        })


        conn = pymysql.connect(
            database=db, user=user, password=password, host=host, port=port,
            use_unicode=True, charset=charset,autocommit=True, conv=conv,
            client_flag=pymysql.constants.CLIENT.INTERACTIVE,
            max_allowed_packet=1024 * 1024 * 1024,
        )

        if hasattr(self, 'conn'):

'\tuser: %r'
            '\thost: %r'
            '\tport: %r'
            '\tsocket: %r'
            '\tcharset: %r'
            '\tlocal_infile: %r'
            '\tssl: %r'
            '\tssh_user: %r'
            '\tssh_host: %r'
            '\tssh_port: %r'
            '\tssh_password: %r'
            '\tssh_key_filename: %r',
            db, user, host, port, socket, charset, local_infile, ssl,
            ssh_user, ssh_host, ssh_port, ssh_password, ssh_key_filename
        )
        conv = conversions.copy()
        conv.update({
            FIELD_TYPE.TIMESTAMP: lambda obj: (convert_mysql_timestamp(obj) or obj),
            FIELD_TYPE.DATETIME: lambda obj: (convert_datetime(obj) or obj),
            FIELD_TYPE.TIME: lambda obj: (convert_timedelta(obj) or obj),
            FIELD_TYPE.DATE: lambda obj: (convert_date(obj) or obj),
        })

        defer_connect = False

        if ssh_host:
            defer_connect = True

        conn = pymysql.connect(
            database=db, user=user, password=password, host=host, port=port,
            unix_socket=socket, use_unicode=True, charset=charset,
            autocommit=True, client_flag=pymysql.constants.CLIENT.INTERACTIVE,