""" Calculator
----------------------------------------
"""
def addition ():
    print("Addition")
    n = float(input("Enter the number: "))
    t = 0 //Total number enter
    ans = 0
    while n != 0:
        ans = ans + n
        t+=1
        n = float(input("Enter another number (0 to calculate): "))
    return [ans,t]
def subtraction ():
    print("Subtraction");
    n = float(input("Enter the number: "))
    t = 0 //Total number enter
    sum = 0
    while n != 0:
        ans = ans - n
        t+=1
        n = float(input("Enter another number (0 to calculate): "))
    return [ans,t]
def multiplication ():
    print("Multiplication")
    n = float(input("Enter the number: "))
    t = 0 //Total number enter
    ans = 1
    while n != 0:
        ans = ans * n
        t+=1
        n = float(input("Enter another number (0 to calculate): "))
    return [ans,t]
def average():
    an = []
    an = addition()
    t = an[1]
    a = an[0]
    ans = a / t
    return [ans,t]
// main...
while True:
    list = []
    print(" My first python program!")
    print(" Simple Calculator in python by Malik Umer Farooq")
    print(" Enter 'a' for addition")
    print(" Enter 's' for substraction")
    print(" Enter 'm' for multiplication")
    print(" Enter 'v' for average")
    print(" Enter 'q' for quit")
    c = input(" ")
    if c != 'q':
        if c == 'a':
            list = addition()
            print("Ans = ", list[0], " total inputs ",list[1])
        elif c == 's':
            list = subtraction()
            print("Ans = ", list[0], " total inputs ",list[1])
        elif c == 'm':
            list = multiplication()
            print("Ans = ", list[0], " total inputs ",list[1])
        elif c == 'v':
            list = average()
            print("Ans = ", list[0], " total inputs ",list[1])
        else:
            print ("Sorry, invilid character")
    else:
        break

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])

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

from statistics import median, mean, mode

def print_stats(array):
  print(array)
  print("median =", median(array))
  print("mean   =", mean(array))
  print("mode   =", mode(array))
  print()

print_stats([1, 2, 3, 3, 4])
print_stats([1, 2, 3, 3])

https://codecatch.net/post/06c9f5b7-1e00-40dc-b436-b8cccc4b69be

bytes_data = b'Hello, World!'
string_data = bytes_data.decode('utf-8')
print("String:", string_data)