Question about python sklearn,

Let say i have a column. It has red blue green and orange. Let say I want to make a bar graph showing how many time this color appeared. How would I do this?

How would I count the number of time the type of color appeared ?

example:

object	color
car	red
ball	orange
money	green
book	red
leaf	green
sea	blue
Lapis	blue
sky	blue
Sapphire	blue
grass	green