def _is_valid_input_row(row, conf):
    """
    Filters blank rows and applies the optional configuration filter
    argument if necessary.

    :param row: the input row
    :param config: the configuration
    :return: whether the row should be converted
    """
    # Filter blank rows.
    if all(value == None for value in row):
        return False
    # Apply the config filter, if any.
    return conf.in_filter(row, conf.in_col_ndx_map) if conf.in_filter else True