Scatter Plot using Color

Greetings,

I am trying to make a scatter plot with each marker having an individual color.

What am I doing wrong?

x = [ 4, 5, 6]
y = [ 7, 8, 9]
size = [ 6,7,8]
color = [ ‘r’, ‘b’, ‘g’]
scatter( x, y, s = size, c = color)
show()

I get the following error:

AttributeError: ‘list’ object has no attribute ‘astype’

Any suggestions would be appreciated!