primes=[]
products=[]

def prime(num):
    if num > 1:
        for i in range(2,num):
            if (num % i) == 0:
                return False
        else:
            primes.append(num)
            return True

for n in range(30,1000):
    if len(primes) >= 20:
        break;
    else:
        prime(n)

for previous, current in zip(primes[::2], primes[1::2]):
    products.append(previous * current)
    
print (products)

# Python code to find the URL from an input string
# Using the regular expression
import re

def Find(string):

	# findall() has been used
	# with valid conditions for urls in string
	regex = r"(?i)\b((?:https?://|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z]{2,4}/)(?:[^\s()<>]+|\(([^\s()<>]+|(\([^\s()<>]+\)))*\))+(?:\(([^\s()<>]+|(\([^\s()<>]+\)))*\)|[^\s`!()\[\]{};:'\".,<>?«»“”‘’]))"
	url = re.findall(regex,string)	
	return [x[0] for x in url]
	
# Driver Code
string = 'My Profile: https://codecatch.net'
print("Urls: ", Find(string))

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

""" 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

list_1 = [1,2,3,4,5,6,7,8,9]
cubed = map(lambda x: pow(x,3), list_1)
print(list(cubed))

#Results
#[1, 8, 27, 64, 125, 216, 343, 512, 729]

my_list = ["blue", "red", "green"]

#1- Using sort or srted directly or with specifc keys
my_list.sort() #sorts alphabetically or in an ascending order for numeric data 
my_list = sorted(my_list, key=len) #sorts the list based on the length of the strings from shortest to longest. 
# You can use reverse=True to flip the order

#2- Using locale and functools 
import locale
from functools import cmp_to_key
my_list = sorted(my_list, key=cmp_to_key(locale.strcoll))