def add_converter(converter_key, func):
    """Adds a new converter to the converters dict"""
    if not converter_key.startswith("@"):
        converter_key = f"@{converter_key}"

    converters[converter_key] = wraps(func)(
        lambda value: value.set_casting(func)
        if isinstance(value, Lazy)
        else Lazy(
            value,
            casting=func,
            formatter=BaseFormatter(lambda x, **_: x, converter_key),
        )
    )
Adds a new converter to the converters dict
dynaconf/utils/parse_conf.py