def integrations_required_keys(modules:list) -> set:
    """
    Gets the variables that the external integrations need to function

    :param modules: Integration initialization modules

    :return: The keys required to initialize all the integrations for this API
    """
    req_keys = set()
    for module in modules:
        keys = getattr(module, "REQ_EXT_VARS", None)
        if keys is None:
            continue
        req_keys.update(keys)

    return req_keys