def interpolate(resource, *args):
    """
    Return a string representing the resource.

    Example:
        >>> interpolate("var", "region")
        ${var.region}
        >>> interpolate("module", "vpc", "network")
        ${module.vpc.network}

    :param resource str: resource name
    :param args list(str): a list of strings representing the Variable
        attributes to interpolate.
    :return str: a string representation of the resource and its arguments if
        any.
    """
    return f"${{{resource}.{'.'.join(args)}}}"