input: Write a function to rewrite the given Python code by introducing list comprehensions. The function should take no input and return the updated list.
  assert rewrite_code()==[2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
  assert rewrite_code()==[2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
  assert rewrite_code()==[2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
  assert rewrite_code()==[2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
  assert rewrite_code()==[2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
output: def rewrite_code():
      return [i for i in range(2, 21, 2)]