input: 
  def removeDuplicates(arr):
      """ Given an array of strings, removes all duplicates and returns the resulting array.
      
      >>> removeDuplicates(['a', 'b', 'a', 'c', 'c', 'd'])
      ['a', 'b', 'c', 'd']
      >>> removeDuplicates([])
      []
      """
      result = []
  
      # traverse for all elements
      for i in arr:
  
          # check if exists in result
          if i not in result:
              result.append(i)
  
      # return result
      return result
  
output:     result = []
  
      # traverse for all elements
      for i in arr:
  
          # check if exists in result
          if i not in result:
              result.append(i)
  
      # return result
      return result