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

def print_pyramid_pattern(n):
     
    # outer loop to handle number of rows
    # n in this case
    for i in range(0, n):
     
        # inner loop to handle number of columns
        # values changing acc. to outer loop
        for j in range(0, i+1):
         
            # printing stars
            print("* ",end="")
      
        # ending line after each row
        print("\r")
 
print_pyramid_pattern(10)

magnitude = lambda bits: 1_000_000_000_000_000_000 % (2 ** bits)
sign = lambda bits: -1 ** (1_000_000_000_000_000_000 // (2 ** bits))

print("64 bit sum:", magnitude(64) * sign(64))
print("32 bit sum:", magnitude(32) * sign(32))
print("16 bit sum:", magnitude(16) * sign(16))

# Python code to demonstrate
# method to remove i'th character
# Naive Method

# Initializing String
test_str = "CodeCatch"

# Printing original string
print ("The original string is : " + test_str)

# Removing char at pos 3
# using loop
new_str = ""

for i in range(len(test_str)):
	if i != 2:
		new_str = new_str + test_str[i]

# Printing string after removal
print ("The string after removal of i'th character : " + new_str)

# 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]),

# importing the modules
import os
import shutil

# getting the current working directory
src_dir = os.getcwd()

# printing current directory
print(src_dir) 

# copying the files
shutil.copyfile('test.txt', 'test.txt.copy2') #copy src to dst

# printing the list of new files
print(os.listdir())