from collections import defaultdict

def collect_dictionary(obj):
  inv_obj = defaultdict(list)
  for key, value in obj.items():
    inv_obj[value].append(key)
  return dict(inv_obj)
  
ages = {
  'Peter': 10,
  'Isabel': 10,
  'Anna': 9,
}
collect_dictionary(ages) # { 10: ['Peter', 'Isabel'], 9: ['Anna'] }

# function which return reverse of a string
def isPalindrome(s):
    return s == s[::-1]
 
# Driver code
s = "malayalam"
ans = isPalindrome(s)
 
if ans:
    print("Yes")
else:
    print("No")

#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 random

class Node:

    def __init__(self, c):

        self.left = None
        self.right = None
        self.color = c
    
    def SetColor(self,c) :
        self.color = c

    def PrintNode(self) :
        print(self.color)

def insert(s, root, i, n):
    if i < n:
        temp = Node(s[i]) 
        root = temp 
        root.left = insert(s, root.left,2 * i + 1, n) 
        root.right = insert(s, root.right,2 * i + 2, n)
    return root
  

def MakeTree(s) :
    list = insert(s,None,0,len(s))
    return list


def MakeSet() :
    s = []
    count = random.randint(7,12)
    for _ in range(count) :
        color = random.randint(0,1) == 0 and "Red" or "White"
        s.append(color)
    return s

def ChangeColor(root) :
    if (root != None) :
        if (root.color == "White") :
            root.SetColor("Red")
        ChangeColor(root.left)
        ChangeColor(root.right)


def PrintList(root) :
    if root.left != None :
        PrintList(root.left)
    else :
        root.PrintNode()
    if root.right != None :
        PrintList(root.right)
    else :
        root.PrintNode()


t1 = MakeTree(MakeSet())
print("Original Colors For Tree 1:\n")
PrintList(t1)
ChangeColor(t1)
print("New Colors For Tree 1:\n")
PrintList(t1)

t2 = MakeTree(MakeSet())
print("Original Colors For Tree 2:\n")
PrintList(t2)
ChangeColor(t2)
print("New Colors For Tree 2:\n")
PrintList(t2)

t3 = MakeTree(MakeSet())
print("Original Colors For Tree 3:\n")
PrintList(t3)
ChangeColor(t3)
print("New Colors For Tree 3:\n")
PrintList(t3)

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])

# Python program for implementation of Bogo Sort
import random

# Sorts array a[0..n-1] using Bogo sort
def bogoSort(a):
	n = len(a)
	while (is_sorted(a)== False):
		shuffle(a)

# To check if array is sorted or not
def is_sorted(a):
	n = len(a)
	for i in range(0, n-1):
		if (a[i] > a[i+1] ):
			return False
	return True

# To generate permuatation of the array
def shuffle(a):
	n = len(a)
	for i in range (0,n):
		r = random.randint(0,n-1)
		a[i], a[r] = a[r], a[i]

# Driver code to test above
a = [3, 2, 4, 1, 0, 5]
bogoSort(a)
print("Sorted array :")
for i in range(len(a)):
	print ("%d" %a[i]),