Write a function which will take one string argument containing characters between a-z, and should remove all repeated characters (duplicates) in the string.

removeduplicates.js

/*
Write a function which will take one string argument containing characters between a-z, and should remove all repeated characters (duplicates) in the string.

Python
The function should be called remove_duplicates and should return a tuple with two values:

A new string with only unique, sorted characters.
The total number of duplicates dropped.
For example:

remove_duplicates('aaabbbac') => ('abc', 5)
remove_duplicates('a') => ('a', 0)
remove_duplicates('thelexash') => ('aehlstx', 2)
JavaScript
The function should be called removeDuplicates and eturn an object literal containing a 'uniques' property, which should be the sorted input string but without any duplicates or special characters.
The returned object should also have a 'duplicates' propoerty which should represent the total number of duplicate characters dropped

For example

removeDuplicates('th#elex_ash?')
Returns

 {uniques: 'aehlstx', duplicates: 2}
*/

function removeDuplicates(str){
  let uniques = str.split('').sort().filter(function(item, pos, self) {
      return self.indexOf(item) == pos;
    }).join('');
  let duplicates = str.length - uniques.length;
  uniques = uniques.replace(/[`~!@#$%^&*()_|+\-=?;:'",.<>\{\}\[\]\\\/]/gi, '');
  return {'uniques':uniques, 'duplicates': duplicates};
}