Creating a list of non-repetitive elements from repetitive-elemets list. Using list-comprehansion only

How can I convert this "for-loop" below to "list-comprehension? I want to create a list of non-repetitive elements from repetitive-elemets list.

many_colors = ['red', 'red', 'blue', 'black', 'blue']

colors = []
for c in many_colors:
  if not c in colors:
    colors.append(c)
# colors = ['red', 'blue', 'black']

I tried this (below) but error occurs that colors are not defined.

colors = [c for c in many_colors if not c in colors]

You can use set in python which represents an unordered collection of unique elements.

Use:

colors = list(set(many_colors))
print(colors)

This prints:

['red', 'black', 'blue']