input: Write a function to extract phone numbers that start with '08' from a given list of phone numbers. If the list is empty, return an empty list.
  def extract_numbers_starting_with_08(phone_numbers):
      return [number for number in phone_numbers if number.startswith('08')]
  
  assert extract_numbers_starting_with_08(['0834567', '0945678', '07123456', '08901234', '07890123'])==['0834567', '08901234']
  assert extract_numbers_starting_with_08([])==[]
  assert extract_numbers_starting_with_08(['0912345', '0723456'])==[]
output: def extract_numbers_starting_with_08(phone_numbers):
      return [number for number in phone_numbers if number.startswith('08')]