input: Write a function to remove duplicate entries from a list and return the list containing only unique elements.
  
  def removeDuplicates(input): 
      final_list = [] 
      for num in input: 
          if num not in final_list: 
              final_list.append(num) 
      return final_list 
  
  assert removeDuplicates([1,2,2,3,3,4])==[1,2,3,4]
  assert removeDuplicates([2,2,2,2])==[2]
  assert removeDuplicates([1,2,3,4])==[1,2,3,4]
  assert removeDuplicates([])==[]
  assert removeDuplicates([1])==[1]
output: def removeDuplicates(input): 
      final_list = [] 
      for num in input: 
          if num not in final_list: 
              final_list.append(num) 
      return final_list