input: Write a function to optimize the given objective function using the scipy.optimize module. The function should return the optimized values of the variables obtained by minimizing the objective function. The function should be named 'optimize' and should accept no parameters.
  assert list(optimize()) == [-0.0, -0.0, -0.0]
  assert list(optimize()) == [-0.0, -0.0, -0.0]
  assert list(optimize()) == [-0.0, -0.0, -0.0]
  assert list(optimize()) == [-0.0, -0.0, -0.0]
  assert list(optimize()) == [-0.0, -0.0, -0.0]
output: 
  from scipy.optimize import minimize
  
  def optimize():
      def objective(x):
          return x[0]**2 + x[1]**2 + x[2]**2
      
      result = minimize(objective, [0, 0, 0])
      return result.x
  