def max_n(lst, n = 1):
  return sorted(lst, reverse = True)[:n]

max_n([1, 2, 3]) # [3]
max_n([1, 2, 3], 2) # [3, 2]

class Rectangle:
    pass

class Square(Rectangle):
    pass

rectangle = Rectangle()
square = Square()

print(isinstance(rectangle, Rectangle))  # True
print(isinstance(square, Rectangle))     # True
print(isinstance(square, Square))        # True
print(isinstance(rectangle, Square))     # False

def byte_size(s):
  return len(s.encode('utf-8'))
  
byte_size('😀') # 4
byte_size('Hello World') # 11

print("test")

#Python 3: Fibonacci series up to n
def fib(n):
 a, b = 0, 1
 while a < n:
     print(a, end=' ')
     a, b = b, a+b
 print()
fib(1000)

import copy
begining = [False,False,False,False,False,None,True,True,True,True,True]
#False = black True = white
its = [0]
def swap(layout, step):
    layoutCopy = copy.deepcopy(layout)
    layoutCopy[(step[0]+step[1])], layoutCopy[step[1]] = layoutCopy[step[1]], layoutCopy[(step[0]+step[1])]
    return layoutCopy
def isSolved(layout):
    for i in range(len(layout)):
        if(layout[i] == False):
            return (i >= (len(layout)/2))
def recurse(layout, its, steps = []):
    if isSolved(layout):
        its[0] += 1
        print(layout,list(x[0] for x in steps))
        return
    step = None
    for i in range(len(layout)):
        if(layout[i] == None):
            if(i >= 1): #If the empty space could have something to the left
                if(layout[i - 1] == False):
                    step = [-1,i]
                    recurse(swap(layout,step), its, (steps+[step]))
                if(i > 1): #If the empty space could have something 2 to the left
                    if(layout[i - 2] == False):
                        step = [-2,i]
                        recurse(swap(layout,step), its, (steps+[step]))
            if(i < (len(layout)-1)): #If the empty space could have something to the right
                if(layout[i + 1] == True):
                    step = [1,i]
                    recurse(swap(layout,step), its, (steps+[step]))
                if(i < (len(layout)-2)): #If the empty space could have something to the right
                    if(layout[i + 2] == True):
                        step = [2,i]
                        recurse(swap(layout,step), its, (steps+[step]))
    its[0] += 1
    #return None
recurse(begining,its,[])
print(its[0])