input: Write a function to rewrite the given Python code using list comprehensions. The original code initializes an empty list and then iterates through numbers from 1 to 20, appending even numbers to the list. The function should return the list of even numbers using list comprehension.
  assert rewrite_even_numbers() == [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
output: def rewrite_even_numbers():
      return [i for i in range(1, 21) if i % 2 == 0]