Particle Class - Python

Example Python class:

class particle:
    def __init__(self, position=Vector([0,0,0])):
        self.position = position
        self.velocity = Vector([uniform(-3,3), 8, uniform(-3,3)])
        self.color = [uniform(.5,1), uniform(0,1), uniform(0,0.5)]
    def update(self, dt):
        self.position += self.velocity * dt
        self.velocity += gravity * dt

class particleSystem:
    def __init__(self):
        self.particles = []
    def addParticles(self, num):
        for i in range(0,num):
            self.particles.append(particle())
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