input: Write a function to generate a Fibonacci sequence up to a maximum value.
  assert fibonacci_sequence(10) == [1, 1, 2, 3, 5, 8]
  assert fibonacci_sequence(1) == [1, 1]
  assert fibonacci_sequence(20) == [1, 1, 2, 3, 5, 8, 13]
output: def fibonacci_sequence(max_value):
      if max_value < 1:
          return []
      sequence = [1, 1]
      while True:
          next_value = sequence[-1] + sequence[-2]
          if next_value > max_value:
              break
          sequence.append(next_value)
      return sequence