How to remove duplicate in a list?

Python
#1

My list contains many duplicates values and I want to remove all duplicates and make it unique. For this purpose, I have developed a code but it is giving error to me. I’m not getting what error is trying to communicate. Here it is:

Error:

NameError                                 Traceback (most recent call last)
Cell In[1], line 5
      3 # Remove duplicates using a loop
      4 for item in my_list:
----> 5     if item not in new_list:
      6         new_list.append(item)
      8 print(new_list)

NameError: name 'new_list' is not defined

Here is my code that I wrote:

Can someone correct my mistakes? If you know any other method, I would appreciate it for sharing it with me.