Gets the corresponding class name for the given error code,
    this either being an integer (thus base error name) or str.

def _get_class_name(error_code):
    """
    Gets the corresponding class name for the given error code,
    this either being an integer (thus base error name) or str.
    """
    if isinstance(error_code, int):
        return KNOWN_BASE_CLASSES.get(
            error_code, 'RPCError' + str(error_code).replace('-', 'Neg')
        )

    return snake_to_camel_case(
        error_code.replace('FIRSTNAME', 'FIRST_NAME').lower(), suffix='Error')