code: function isDflowFun (f) {
    var isFunction = typeof f === 'function'
    var hasFuncsObject = typeof f.funcs === 'object'
    var hasGraphObject = typeof f.graph === 'object'
    var hasValidGraph = true
  
    if (!isFunction || !hasFuncsObject || !hasGraphObject) return false
  
    if (isFunction && hasGraphObject && hasFuncsObject) {
      try {
        validate(f.graph, f.funcs)
      } catch (ignore) {
        hasValidGraph = false
      }
    }
  
    return hasValidGraph
  }
docs: Duct tape for dflow functions.
  
  @param {Function} f
  
  @returns {Boolean} ok, it looks like a dflowFun