#' load functions
#' @export
#'
load_aif360_lib <- function() {
  e <- globalenv()
  bindings <- c("datasets", "metrics", "pre_algo", "in_algo", "post_algo", "tf")
  if (!all(bindings %in% ls(e))){
    e$datasets <- import("aif360.datasets")
    e$metrics <- import("aif360.metrics")
    e$pre_algo <- import("aif360.algorithms.preprocessing")
    e$in_algo <- import("aif360.algorithms.inprocessing")
    e$post_algo <- import("aif360.algorithms.postprocessing")
    e$tf <- import("tensorflow")
    lockBinding("datasets", e)
    lockBinding("metrics", e)
    lockBinding("pre_algo", e)
    lockBinding("in_algo", e)
    lockBinding("post_algo", e)
    lockBinding("tf", e)
  } else {
    message("The aif360 functions have already been loaded. You can begin using the package.")
  }
}