clone seems to be appending data

[jloveric]

The clone function is appending functions to my code. My code looks like this

console.log(script)
let input = clone(script)
console.log('----------------')
console.log(input)
process.exit(0)

and outputs this (this first data is the input, the data below ---------- is the output). The output
has list data (I think appended to it)

{ data: 
   [ { pattern: [Array],
       response: [Array],
       details: [Object],
       intent: [Array],
       phraseClass: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] } ] }
----------------
{ data: 
   [ { pattern: [Array],
       response: [Array],
       details: [Object],
       intent: [Array],
       phraseClass: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     { pattern: [Array], intent: [Array] },
     __class__: { [Function: list] __name__: 'list' },
     __iter__: [Function],
     __getslice__: [Function],
     __setslice__: [Function],
     __repr__: [Function],
     __str__: [Function],
     append: [Function],
     clear: [Function],
     extend: [Function],
     insert: [Function],
     remove: [Function],
     index: [Function],
     py_pop: [Function],
     py_sort: [Function],
     __add__: [Function],
     __mul__: [Function],
     __rmul__: [Function],
     __bindexOf__: [Function],
     add: [Function],
     discard: [Function],
     isdisjoint: [Function],
     issuperset: [Function],
     issubset: [Function],
     union: [Function],
     intersection: [Function],
     difference: [Function],
     symmetric_difference: [Function],
     py_update: [Function],
     __eq__: [Function],
     __ne__: [Function],
     __le__: [Function],
     __ge__: [Function],
     __lt__: [Function],
     __gt__: [Function] ] }

Is this the intended result? How do I get rid of the extra 'list' data?