input: Write a python function to normalize a list of numbers using numpy.
  assert np.allclose(normalize([1, -2, 7, 5, 2]), [0.1245256, -0.2490512, 0.8736233, 0.6207616, 0.2490512])
  assert np.allclose(normalize([3, 4]), [0.6, 0.8])
  assert np.allclose(normalize([0, 0, 0]), [0, 0, 0])
output: import numpy as np
  
  def normalize(lst):
      arr = np.array(lst)
      norm = np.linalg.norm(arr)
      if norm == 0:
          return arr
      return arr / norm