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

x[cat_var].isnull().sum().sort_values(ascending=False)

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]

# Python Program to calculate the square root

num = float(input('Enter a number: '))

num_sqrt = num ** 0.5
print('The square root of %0.3f is %0.3f'%(num ,num_sqrt))

# Python program for implementation of Selection
# Sort
import sys
A = [64, 25, 12, 22, 11]

# Traverse through all array elements
for i in range(len(A)):
	
	# Find the minimum element in remaining
	# unsorted array
	min_idx = i
	for j in range(i+1, len(A)):
		if A[min_idx] > A[j]:
			min_idx = j
			
	# Swap the found minimum element with
	# the first element		
	A[i], A[min_idx] = A[min_idx], A[i]

# Driver code to test above
print ("Sorted array")
for i in range(len(A)):
	print("%d" %A[i]),

from time import sleep

def delay(fn, ms, *args):
  sleep(ms / 1000)
  return fn(*args)

delay(lambda x: print(x), 1000, 'later') # prints 'later' after one second