A colorful Trifoil Knot

Some time ago I was looking for a cool way to visualize parametric equations and I started working on the the trefoil knot. It is the simplest example of a nontrivial knot and it can be defined with the following parametric equations:

After a while this snippet came out:

from numpy import linspace,pi,cos,sin
phi = linspace(0,2*pi,100)
x = sin(phi)+2*sin(2*phi)
y = cos(phi)-2*cos(2*phi)
z = -sin(3*phi)

from pylab import scatter,subplot,cm,show
from numpy import abs
s=abs(((y+3)+2)*10)
scatter(x,y,c=x,s=s,edgecolor='w',cmap=cm.gist_rainbow)
scatter(x/1.4,y/1.2,c=x,s=s,edgecolor='w',cmap=cm.gist_rainbow_r)
scatter(x/1.8,y/1.5,c=x,s=s,edgecolor='w',cmap=cm.gist_rainbow)
show()

So, here's my colorful version of the trifold knot:

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